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NSF 61-2007Drinking water system components Health effects


NSF/ANSI 61 – 2007

Drinking water system components Health effects
NSF International Standard/ American National Standard

Developed by a consortium of: ? NSF Intern

ational ? The American Water Works Association Research Foundation ? The Association of State Drinking Water Administrators ? The American Water Works Association

With support from: ? The U. S. Environmental Protection Agency under cooperative agreement #CR-812144

NSF/ANSI 61 – 2007

NSF International, an independent, notfor-profit, non-governmental organization, is dedicated to being the leading global provider of public health and safetybased risk management solutions while serving the interests of all stakeholders.

This Standard is subject to revision. Contact NSF to confirm this revision is current. Users of this Standard may request clarifications and interpretations, or propose revisions by contacting: Chair, Joint Committee on Drinking Water Additives c/o NSF International 789 North Dixboro Road, P. O. Box 130140 Ann Arbor, Michigan 48113-0140 USA Phone: (734) 769-8010 Telex: 753215 NSF INTL FAX: (734) 769-0109 E-mail: info@nsf.org Web: http://www.nsf.org

NSF/ANSI 61 – 2007

NSF International Standard/ American National Standard for Drinking Water Additives ―

Drinking water system components ― Health effects

Standard Developer NSF International

Adopted March 27, 2007 NSF International Board of Directors Designated as an ANSI Standard March 27, 2007 American National Standards Institute

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Prepared by The NSF Joint Committee on Drinking Water Additives Recommended for Adoption by The NSF Council of Public Health Consultants Adopted by The NSF Board of Directors June 1988 Revised October 1988 Revised May 1990 Revised May 1991 Revised May 1992 Revised September 1994 Revised January 1995 Revised July 1996 Revised September 1996 Revised November 1996 Revised January 1997 Revised January 1997 Revised March 1997 Revised July 1997 Revised November 1998 Revised January 1999 Revised November 1999 Revised September 2000 Revised November 2000 Revised February 2001 Addendum September 2001 Revised July 2002 Addendum August 2002 Editorial Revision February 2002 Revised September 2003 Editorial Revision October 2003 Revised November 2004 Addendum March 2005 Revised October 2005 Revised March 2007

Published by NSF International PO Box 130140, Ann Arbor, Michigan 48113-0140, USA
For ordering copies or for making inquiries with regard to this Standard, please reference the designation “NSF/ANSI 61 – 2007.”

Copyright 2007 NSF International Previous editions ? 2005, 2004, 2003, 2002, 2001, 2000, 1999, 1998, 1997, 1996, 1995, 1994, 1992, 1991, 1990, 1988
Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from NSF International.

Printed in the United States of America.

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Disclaimers1 NSF, in performing its functions in accordance with its objectives, does not assume or undertake to discharge any responsibility of the manufacturer or any other party. The opinions and findings of NSF represent its professional judgment. NSF shall not be responsible to anyone for the use of or reliance upon this Standard by anyone. NSF shall not incur any obligation or liability for damages, including consequential damages, arising out of or in connection with the use, interpretation of, or reliance upon this Standard. NSF Standards provide basic criteria to promote sanitation and protection of the public health. Provisions for mechanical and electrical safety have not been included in this Standard because governmental agencies or other national standards-setting organizations provide safety requirements. Participation in NSF Standards development activities by regulatory agency representatives (federal, local, state) shall not constitute their agency's endorsement of NSF or any of its Standards. Preference is given to the use of performance criteria measurable by examination or testing in NSF Standards development when such performance criteria may reasonably be used in lieu of design, materials, or construction criteria. The illustrations, if provided, are intended to assist in understanding their adjacent standard requirements. However, the illustrations may not include all requirements for a specific product or unit, nor do they show the only method of fabricating such arrangements. Such partial drawings shall not be used to justify improper or incomplete design and construction. Unless otherwise referenced, the annexes are not considered an integral part of NSF Standards. The annexes are provided as general guidelines to the manufacturer, regulatory agency, user, or certifying organization.

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The information contained in this Disclaimer is not part of this American National Standard (ANS) and has not been processed in accordance with ANSI’s requirements for an ANS. Therefore, this Disclaimer may contain material that has not been subjected to public review or a consensus process. In addition, it does not contain requirements necessary for conformance to the Standard.

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Contents 1 Purpose, scope, and normative references............................................................................................ 1 1.1 Purpose............................................................................................................................................ 1 1.2 Scope ............................................................................................................................................... 1 1.3 Normative references....................................................................................................................... 1 1.4 Limitations ........................................................................................................................................ 3 1.5 Alternate products or materials ........................................................................................................ 3 1.6 Significant figures............................................................................................................................. 4 Definitions ............................................................................................................................................... 4 General requirements............................................................................................................................. 6 3.1 General ............................................................................................................................................ 6 3.2 Information and formulation requirements ....................................................................................... 6 3.3 Identification of analytes................................................................................................................... 7 3.4 Products manufactured from annex C acceptable materials ........................................................... 8 Table 3.1 – Material-specific analyses ................................................................................................... 9 Pipes and related products................................................................................................................... 11 4.1 Scope ............................................................................................................................................. 11 4.2 Definitions ...................................................................................................................................... 11 4.3 General requirements .................................................................................................................... 11 4.4 Sample requirements ..................................................................................................................... 12 4.5 Extraction procedures .................................................................................................................... 12 4.6 Analysis.......................................................................................................................................... 17 4.7 Normalization of contaminant concentrations................................................................................ 17 4.8 Evaluation of contaminant concentrations ..................................................................................... 19 Table 4.1 – Example single time point conditioning schedule.............................................................. 19 Table 4.2 – Single time point exposure schedule................................................................................. 20 Table 4.3 – Example multiple time point conditioning/exposure schedule........................................... 21 Table 4.4 – Pipes – normalization factors and assumptions................................................................ 22 Table 4.5 – Fittings (installed at regular intervals) – normalization factors and assumptions.............. 23 Table 4.6 – Example normalization calculations .................................................................................. 24 Barrier materials ................................................................................................................................... 25 5.1 Scope ............................................................................................................................................. 25 5.2 Definitions ...................................................................................................................................... 25 5.3 General requirements .................................................................................................................... 26 5.4 Sample requirements ..................................................................................................................... 26 5.5 Extraction procedures .................................................................................................................... 27 5.6 Analysis of extraction water ........................................................................................................... 30 5.7 Normalization ................................................................................................................................. 30 5.8 Evaluation of contaminant concentrations ..................................................................................... 32 Table 5.1 – Paint and coating system sample preparation .................................................................. 33 Table 5.2 – Single time point exposure sequence ............................................................................... 33 Table 5.3 – Multiple time point exposure sequence ............................................................................. 33 Table 5.4 – Surface-area-to-volume ratios for tanks or storage vessels.............................................. 34 Joining and sealing materials ............................................................................................................... 35 6.1 Coverage........................................................................................................................................ 35 6.2 Definitions ...................................................................................................................................... 35 6.3 Material and extraction testing requirements ................................................................................. 35 6.4 Items of special significance .......................................................................................................... 35 Process media ...................................................................................................................................... 35

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7.1 Scope ............................................................................................................................................. 35 7.2 Definitions ...................................................................................................................................... 35 7.3 General requirements .................................................................................................................... 36 7.4 Sample requirements ..................................................................................................................... 37 7.5 Extraction procedures .................................................................................................................... 37 7.6 Analysis.......................................................................................................................................... 39 7.7 Normalization ................................................................................................................................. 39 7.8 Evaluation of contaminant concentrations ..................................................................................... 40 Table 7.1 – Product-specific minimum test batteries for process media products............................... 41 Table 7.2 – Process media exposure weight-per-volume ratios .......................................................... 41 Table 7.3 – Maximum conditioning expansion rates for filtration and adsorption media ..................... 42 Table 7.4 – Exposure schedule for process media of ≥ 0.25 mm in diameter ..................................... 42 8 Mechanical devices .............................................................................................................................. 42 8.1 Coverage........................................................................................................................................ 42 8.2 Definitions ...................................................................................................................................... 42 8.3 Device, component, or material requirements ............................................................................... 43 8.4 In-line devices, components, and materials................................................................................... 43 8.5 Chemical feeders and generators.................................................................................................. 43 8.6 Other mechanical devices, components, and materials ................................................................ 44 Table 8.1 – Examples of mechanical devices ...................................................................................... 44 Mechanical plumbing devices............................................................................................................... 45 9.1 Coverage........................................................................................................................................ 45 9.2 Definitions ...................................................................................................................................... 46 9.3 Device, component, or material requirements ............................................................................... 46 9.4 Exposure and normalization .......................................................................................................... 47 9.5 Evaluation of normalized contaminant concentrations .................................................................. 47

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Annex A ..........................................................................................................................................A1 A.1 General requirements...........................................................................................................................A1 A.2 Definitions ..........................................................................................................................................A1 A.3 Data requirements for published risk assessments..............................................................................A4 A.4 Data requirements for new or updated risk assessments ....................................................................A5 A.5 Data requirements for evaluating short-term exposures ......................................................................A6 A.6 Risk estimation for published assessments .........................................................................................A7 A.7 Risk estimation using new and updated risk assessments ..................................................................A8 A.8 Risk estimation for short-term exposure (STEL calculation) ..............................................................A14 A.9 Development of chemical class-based evaluation criteria .................................................................A15 A.10 Key elements of a risk assessment for drinking water additive chemicals ..................................A16 Table A1 – Qualitative risk assessment data requirements......................................................................A25 Table A2 – Quantitative risk assessment data requirements ...................................................................A26 Table A3 – TACs for qualitative risk assessment .....................................................................................A27 Table A4 – Uncertainty factors..................................................................................................................A27 Annex B ..........................................................................................................................................B1 B.1 Background ..........................................................................................................................................B1 B.2 General evaluation requirements .........................................................................................................B1 B.3 Joining and sealing materials ...............................................................................................................B4 B.4 Mechanical devices ..............................................................................................................................B6 B.5 Mechanical plumbing devices...............................................................................................................B8 B.6 Collection and preservation of extraction media after exposure ........................................................B10 B.7 Analysis methods................................................................................................................................B11 B.8 Normalization......................................................................................................................................B17 B.9 Extraction water preparation...............................................................................................................B22 Figure B1 – Exposure sequence for mechanical plumbing device ...........................................................B26

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Table B1 – NSF/ANSI 61 products ...........................................................................................................B27 Table B2 – Exposure summary.................................................................................................................B27 Table B3 – Extraction water selection.......................................................................................................B28 Table B4 – Test samples joining and sealing materials............................................................................B28 Table B5 – Exposure sequence for cold applications...............................................................................B28 Table B6 – Exposure sequence for hot applications ................................................................................B28 Table B7 – Product exposure1 .................................................................................................................B29 Table B8 – In-line device exposure sequence ..........................................................................................B29 Table B9 – Other mechanical device exposure sequence .......................................................................B29 Table B10 – Extractant water collection and preservation........................................................................B30 Table B11 – Normalization factors, assumptions, and examples pertaining to – water main joining and sealing materials .......................................................................................................................................B31 Table B12 – Data available for determination of lead test statistic...........................................................B37 Table B13 – Values of k1 for determining test statistic Q .........................................................................B37 Table B14 – Values of k2 for determining retest statistic R ......................................................................B37 Table B15 – 1-L volume of extraction water .............................................................................................B38 Annex C C1 C.1 Purpose C1 C.2 Evaluation of acceptable materials.......................................................................................................C1 C.3 Extraction testing ..................................................................................................................................C1 C.4 Documentation......................................................................................................................................C1 Table C1 – Acceptable materials ................................................................................................................C2 Annex D D1 D.1 General D1 D.2 USEPA and Health Canada drinking water criteria ..............................................................................D1 D.3 NSF International peer-reviewed drinking water criteria ......................................................................D1 D.4 Drinking water criteria based on USEPA guidance concentrations .....................................................D2 D.5 Threshold of evaluation (TOE) chemical list.........................................................................................D2 Table D1 – U. S. Environmental Protection Agency and Health Canada...................................................D3 NSF/ANSI 61 drinking water criteria ...........................................................................................................D3 Table D2 – NSF International peer-reviewed drinking water criteria ..........................................................D9 Table D3 – Drinking water criteria based on USEPA guidance concentrations ...................................... D12 Table D4 – Threshold of evaluation chemicals1 ...................................................................................... D23 Annex E ..........................................................................................................................................E1 E.1 General ..........................................................................................................................................E1 E.2 NSF International drinking water criteria (not externally peer-reviewed) .............................................E1 E.3 Informational threshold of evaluation chemicals ..................................................................................E2 Table E1 – NSF International drinking water criteria (not externally peer reviewed)..................................E3 Table E2 – Threshold of evaluation chemicals having datasets from which specific TAC/SPAC values, or CBEL values, could be set using Annex A1................................................................................................E5

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Foreword2 In response to a competitive request for proposals from the U.S. Environmental Protection Agency (USEPA), a Consortium led by NSF International (NSF) agreed to develop voluntary third-party consensus standards and a certification program for all direct and indirect drinking water additives. Other members of the Consortium include the American Water Works Association Research Foundation, the Association of State Drinking Water Administrators, the Conference of State Health and Environmental Managers, and the American Water Works Association. (COSHEM has since become inactive as an organization.) Each organization was represented on a steering committee with oversight responsibility for the administration of the cooperative agreement. The Steering Committee provides guidance on overall administration and management of the cooperative agreement. Currently, the member organizations remain active in an oversight role. Two standards for additives products were developed. NSF/ANSI 60 – Drinking water treatment chemicals ― Health effects covers many of the water treatment chemicals, also known as direct additives. This Standard, NSF/ANSI 61 – Drinking water system components ― Health effects, covers all indirect additives products and materials. Testing to determine the potential of a product to impart taste and/or odor to drinking water is not included in this Standard. NSF/ANSI 61 was developed to establish minimum requirements for the control of potential adverse human health effects from products that contact drinking water. It does not attempt to include product performance requirements that are currently addressed in other voluntary consensus standards established by such organizations as the American Water Works Association, the American Society for Testing and Materials, and the American National Standards Institute. Because this Standard complements the performance standards of these organizations, it is recommended that products also meet the appropriate performance requirements specified in the standards of such organizations. NSF/ANSI 61, and subsequent product certification against it, has replaced the USEPA Additives Advisory Program for drinking water system components. USEPA terminated its advisory role in April 1990. For more information with regard to USEPA's actions, refer to the July 7, 1988 Federal Register (53FR25586). This Standard and the accompanying text are intended for voluntary use by certifying organizations, utilities, regulatory agencies, and/or manufacturers as a basis of providing assurances that adequate health protection exists for covered products. Product certification issues, including frequency of testing and requirements for follow-up testing, evaluation, enforcement, and other policy issues, are not addressed by this Standard. Water contact materials in Drinking Water Treatment Units listed under NSF/ANSI 42, 44, 53, 55, 58, and 62 are tested and evaluated under a separate protocol from NSF/ANSI 61 with criteria which were developed specifically for the intended end-use. NSF 61 listing should not be additionally required for acceptance of these listed units for water contact application. This version includes the following revisions: – The requirements in section 5.5, Extraction procedures, have been further clarified to require the average coating application not to exceed the maximum dry film thickness per coat for fieldapplied paint and coatings systems and factory applied or cured systems (Joint Committee Issue 58);

2 The information contained in this Foreword is not part of this American National Standard (ANS) and has not been processed in accordance with ANSI’s requirements for an ANS. Therefore, this Foreword may contain material that has not been subjected to public review or a consensus process. In addition, it does not contain requirements necessary for conformance to the Standard.

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Section 9, Mechanical plumbing devices, has been revised to specifically identify normalization and evaluation of lead and non-lead requirements for side sprayers (Joint Committee Issue 11); The Normalization for endpoint devices, components, and materials, as defined in annex B, has been revised as to clarify how to normalize when the volume of the device is less than 1 Liter (Joint Committee Issue 65); Guidance has been added to Section 1 indicating that the Absolute Method should be used when evaluating analytical results to the specifications of this Standard per ASTM E29-02 (Joint Committee Issue 59); The most recent additions of unregulated contaminants have been incorporated into Tables D2 and D4 in Annex D (Joint Committee Issue 68); and Section 3.2 has been amended to clarify the need to examine process performance and the necessary controls required to provide continued compliance of products (Joint Committee Issue 69).









This Standard was developed by the NSF Joint Committee on Drinking Water Additives using the consensus process described by the American National Standards Institute. Suggestions for improvement of this Standard are welcome. Comments should be sent to Chair, Joint Committee on Drinking Water Additives, c/o NSF International, Standards Department, P. O. Box 130140, Ann Arbor, Michigan 48113-0140, USA.

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Consortium organizations3 NSF International Popularly referred to as NSF, NSF International is a noncommercial agency. It is incorporated under the laws of Michigan as a not-for-profit organization devoted to research, education, and service. It seeks to solve problems involving man and his environment. It wishes to promote health and enrich the quality of life through conserving and improving that environment. Its fundamental principle of operation is to serve as a neutral medium in which business and industry, official regulatory agencies, and the public come together to deal with problems involving products, equipment, procedures, and services related to health and the environment. It is conceived and administered as a public service organization. NSF is perhaps best known for its role in developing standards and criteria for equipment, products, and services that bear upon health. NSF was the lead organization in the Consortium responsible for developing this Standard. NSF conducts research; tests and evaluates equipment, products, and services for compliance with standards and criteria; and grants and controls the use of NSF registered Marks. NSF offers product certification (Listing Services) for all products covered by its standards. Each program has established policies governing the associated product evaluation, Listing Services, follow-up, and enforcement activities. The NSF Listing Mark is widely recognized as a sign that the product or service to which it relates complies with the applicable NSF standard(s). AWWA Research Foundation The mission of the American Water Works Association Research Foundation (AWWARF) is to sponsor practical, applied research on behalf of the drinking water industry of North America. The scope of the research program embraces all aspects of water supply operation, from development and maintenance of water resources to treatment technologies and water quality issues, from storage and distribution system operations to health effects studies and utility planning and management activities. AWWARF serves as the centralized industry institution for planning, managing, and funding cooperative research and development in drinking water, including the subsequent transfer of technology and results for practical application by the water utility community. AWWARF's purpose in this cooperative program is to provide a communication link with the water utilities throughout North America and serve as the focal point for identification of research needs of the water supply industry with respect to the additives program. The Association of State Drinking Water Administrators The Association of State Drinking Water Administrators (ASDWA) is a nonprofit organization whose eligible membership is comprised of drinking water program administrators in each of the 50 states and seven U. S. territories. Through the organization, representatives speak with a collective voice to Congressional committees, the United States Environmental Protection Agency (EPA), professional and trade associations, water utilities, and the general public on issues related to state drinking water programs. With its mission of protecting the public health through assurance of high-quality drinking water, and promoting responsible, reasonable, and feasible drinking water programs at the state and federal levels, the Association is a valued contributor to the consortium, and to the program. It provides the link between the additives program and the state drinking water programs.

The information contained in this section is not part of this American National Standard (ANS) and has not been processed in accordance with ANSI’s requirements for an ANS. Therefore, this section may contain material that has not been subjected to public review or a consensus process. In addition, it does not contain requirements necessary for conformance to the Standard.

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The Conference of State Health and Environmental Managers The Conference of State Health and Environmental Managers (COSHEM), known formerly as the Conference of State Sanitary Engineers (CSSE), is currently inactive as an organization. It brought to the consortium expertise and involvement of state health and environmental program managers. The Conference was the focal point for health concerns of all state environmental programs, including drinking water, wastewater, air, solid and hazardous wastes, radiology, occupational health, and food. A standing committee on water supply focused on drinking water issues and kept the membership informed. The Conference played an important role early in the program through two-way communication with state health and environmental program decisionmakers. American Water Works Association The purpose of the American Water Works Association (AWWA) is to promote public health, safety, and welfare by improving the quality and increasing the quantity of water delivered to the public, and to developing and furthering an understanding of the problems relating thereto by: – advancing the knowledge of the design, construction, operation, water treatment, and management of water utilities; – developing standards for procedures, equipment, and materials used by public water supply systems; – advancing the knowledge of problems involved in the development of resources, production, and distribution of safe and adequate water supplies; – educating the public on the problems of water supply and promoting a spirit of cooperation between consumers and suppliers in solving these problems; and – conducting research to determine the causes of problems with providing a safe and adequate water supply, and proposing solutions thereto in an effort to improve the quality and quantity of the water supply provided to the public. AWWA brings to the Consortium its established position as the largest public drinking water association in North America, with a broad membership that includes utilities, consultants, manufacturers/distributors/ agents, contractors, and other organizations with a direct interest in drinking water.

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? 2007 NSF

NSF/ANSI 61 – 2007

NSF/ANSI Standard for Drinking Water Additives ―

Drinking water system components – Health effects
1 Purpose, scope, and normative references
1.1 Purpose This Standard establishes minimum health effects requirements for the chemical contaminants and impurities that are indirectly imparted to drinking water from products, components, and materials used in drinking water systems. This Standard does not establish performance, taste and odor, or microbial growth support requirements for drinking water system products, components, or materials. 1.2 Scope 1.2.1 This Standard is intended to cover specific materials or products that come into contact with drinking water, drinking water treatment chemicals, or both. The focus of the Standard is evaluation of contaminants or impurities imparted indirectly to drinking water. The products and materials covered include, but are not limited to, process media (carbon, sand, etc.), protective materials (coatings, linings, liners, etc.), joining and sealing materials (solvent cements, welding materials, gaskets, etc.), pipes and related products (pipes, tanks, fittings, etc.), mechanical devices used in treatment/transmission/distribution systems (valves, chlorinators, separation membranes, etc.), and mechanical plumbing devices (faucets, endpoint control valves, etc.). 1.2.2 Point-of-use and point-of-entry drinking water treatment devices are not covered by the scope of this Standard. 1.2.3 Fire hydrants are not covered by the scope of this Standard.

1.3 Normative references The following documents contain requirements that, by reference in this text, constitute requirements of this Standard. APHA, Standard Methods for the Examination of Water and Wastewater, twentieth edition4 ASTM A240/A240M-05. Standard Specification for Chromium and Chromium-Nickel Stainless Steel Plate, Sheet, and Strip for Pressure Vessels and for General Applications5 ASTM A269-04. Standard Specification for Seamless and Welded Austenitic Stainless Steel Tubing for General Service5
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American Public Health Association (APHA), 800 I Street, NW, Washington, DC 20001 ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2859

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ASTM A312/A312M-05. Standard Specification for Seamless, Welded, and Heavily Cold Worked Austenitic Stainless Steel Pipes5 ASTM A789/A789M-05. Standard Specification for Seamless and Welded Ferritic/Austenitic Stainless Steel Tubing for General Service5 ASTM A790/A790M-05. Standard Specification for Seamless and Welded Ferritic/Austenitic Stainless Steel Pipe5 ASTM A815/A815M-04. Standard Specification for Wrought Ferritic, Ferritic/Austenitic, and Martensitic Stainless Steel Piping Fittings5 ASTM C31/C31M-00e1. Standard Practice for Making and Curing Concrete Test Specimens in the Field5 ASTM C109/C109M-99. Standard Test Method for Compressive Strength of Hydraulic Cement Mortars5 ASTM C 183-02. Standard Practice for Sampling and the Amount of Testing of Hydraulic Cement5 ASTM C192/C192M-00. Standard Practice for Making and Curing Concrete Test Specimens in the Laboratory5 ASTM C511-98. Standard Specification for Moist Cabinets, Moist Rooms, and Water Storage Tanks Used in the Testing of Hydraulic Cements and Concretes5 ASTM C778-00. Standard Specification for Standard Sand 5 ASTM D2855-96. Standard Practice for Making Solvent-Cemented Joints with Poly(Vinyl Chloride) (PVC) Pipe and Fittings5 ASTM D3182-89 (1994). Standard Practice for Rubber – Materials, Equipment, and Procedures for Mixing Standard Compounds and Preparing Standard Vulcanized Sheets5 ASTM E29-02 Standard Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications5 ASTM F493-97. Standard Specification for Solvent Cements for Chlorinated Poly(Vinyl Chloride) (CPVC) Plastic Pipe and Fittings5 ANSI/AWWA B100-96. AWWA Standard for Filtering Material6 ANSI/AWWA C652-92. AWWA Standard for Disinfection of Water-Storage Facilities6 NSF/ANSI 60 – 2003. Drinking water treatment chemicals – Health effects OECD, OECD Guidelines for the Testing of Chemicals, May 19967 SSPC-PA2– 2004 Steel Structures Painting Manual Volume 2. Paint Application Specification8
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American Water Works Association (AWWA), 6666 Quincy Avenue, Denver, CO 80235-9913

7 Organization for Economic Cooperation and Development (OECD), 2 Rue Andre-Pascal, 75775 Paris Cedex 16, France 8

SSPC (The Society for Protective Coatings), 40 24th Street, 6th Floor, Pittsburgh, PA 15222-4656

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The Society for Protective Coatings, Steel Structures Painting Manual. Volume 2. Reference Paint Application Specification No. 2 (SSPC-PA2)8 USEPA-570-9-82-002. Manual for the Certification of Laboratories Analyzing Drinking Water, October 1982.9 USEPA-600/4-79-020. Methods for the Chemical Analysis of Water and Wastes, March 19839 USEPA-600/4-80-032. Prescribed Procedures for Measurement of Radioactivity in Drinking Water9 USEPA-600/4-84-053. Methods for Organic Chemical Analysis of Municipal and Industrial Wastewater, June 19849 USEPA, Health Effects Testing Guidelines, 40 CFR Part 79810 USEPA, Good Laboratory Practice Standards, 40 CFR Part 16010 USEPA, Guidelines Establishing Test Procedures for the Analysis of Pollutants, 40 CFR Part 13610 USEPA, National Primary Drinking Water Regulations, 40 CFR Part 14110 USFDA, Good Laboratory Practice for Non-Clinical Laboratory Studies, 21 CFR 5811 USFDA, Toxicological Principles for the Safety Assessment of Direct Food Additives and Color Additives in Food 11 1.4 Limitations The requirements of this Standard are limited to addressing potential health effects, except where specific application and performance standards are referenced. This Standard does not establish taste and odor requirements for drinking water system products and materials. The criteria set forth in this Standard cover products created by good manufacturing practices and generally recognized manufacturing processes. As the presence of unusual or unexpected impurities is frequently dependent upon the method of manufacture and the quality of raw material used, products prepared by other than recognized methods of manufacture or with unusual raw materials shall be fully evaluated in accordance with 3 of this Standard (general requirements). Products that have been evaluated and found to meet other NSF standards having health requirements equivalent to this Standard as indicated in each section shall be acceptable for drinking water applications without separate evaluation under this Standard.12 1.5 Alternate products or materials While specific materials are stipulated in this Standard, drinking water system products or components that incorporate alternate materials shall be acceptable when it is verified that the product or component meets the applicable requirements of the Standard based on its end use.

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USEPA, Environmental Monitoring and Support Laboratory, Cincinnati, OH 45268 Superintendent of Documents, U. S. Government Printing Office, Washington, DC 20402 USFDA, 5600 Fishers Lane, Rockville, MD 20857

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Final acceptance of a product for drinking water application is the responsibility of the appropriate federal, state, or local regulatory agent.

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? 2007 NSF 1.6 Significant figures

NSF/ANSI 61 – 2007

For determining conformance with the specifications in this standard, the Absolute Method in ASTM E29 Standard Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications shall be used.

2 Definitions
Terms used in this Standard that have a specific technical meaning are defined here. 2.1 analytical summary: A list of the analytes and analytical procedures, both chemical and microbiological, that are selected to determine whether a product is compliant to the requirements of the Standard; analytes may be either product-specific or formulation-dependent. 2.2 at the tap: Referring to the point of delivery or point of use for drinking water. 2.3 cold water application: A product application that is not intended to result in exposure for extended periods to water in excess of ambient water temperature. 2.4 contaminant: A physical, chemical, biological, or radiological substance or matter in water.
NOTE – Consistent with the definition in the Federal Safe Drinking Water Act, a contaminant can have either a beneficial or detrimental effect on the potability of water.

2.5 diluted surface area (DSA): The surface area/volume ratio of a product, component, or material calculated using its actual wetted surface area, the field static and/or field flow volumes directed by the standard for the end use for which the product is being evaluated. The calculation shall use the normalization equation specific to that end use. The values for lab surface area and lab volume in the normalization equation shall be entered as 1 for the purposes of this determination causing the DSA ratio to equal the calculated NF factor. Example calculation: For a component of a chemical generator that has an actual surface area of 5 in2, assuming that the static volume of the unit is 6 L, the unit generates 10 L of chemical in a 4-h period and the chemical is dosed to the drinking water stream at 20 ppm (or 10 L of chemical to 500,000 L of treated water). (Refer to annex B for definition of normalization terms): DSA (in2/L) = = = where: SAF = surface area exposed in the field; SAL = surface area exposed in the laboratory; VL = volume of extraction water used in the laboratory; VF(static) = volume of water to which the product is exposed under static conditions; and = NF = N1 * N2 * N4 VF(static) x VF (flowing) x 10 500,000 VTC VWT

SAF x VL x SAL VF(static) 5 1 x 1 6 x 6 10

0.00001 in2/L

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VF(flowing) = volume of water to which the product is exposed under flowing conditions during a period of time equivalent to the laboratory test. VTC = volume of concentrated treatment chemical contacted or generated by the device during a period of time equivalent to the laboratory test VWT = volume of raw water treated with the concentrated chemical when dosed at the prescribed feed rate during a period of time equivalent to the laboratory test 2.6 direct additives: A treatment chemical and its contaminants directly added to water during the production of drinking water. 2.7 distribution system: The system of conduits or the network of pipelines (located primarily in the streets) through which a primary domestic water supply is distributed to consumers. In plumbing codes, this term is applied to all the hot and cold water piping installed in buildings. 2.8 drinking water: Water intended for human consumption. 2.9 good manufacturing practices: The practice of maximizing the purity of products and materials by maintaining and practicing appropriate quality control and quality assurance procedures. 2.10 hot water application: A product application that is intended to result in exposure for extended periods to water that has been raised from ambient temperature. 2.11 indirect additives: Contaminants that are extracted into drinking water through contact with the surfaces of materials, components, or products used for its treatment, storage, transmission, or distribution. 2.12 manufacturer: A corporation, company, or individual that produces, formulates, packages, or repackages products, components, and materials that are intended to be in contact with drinking water. 2.13 maximum contaminant level (MCL): The maximum concentration of a regulated contaminant that is permitted in a public drinking water supply, as defined under the Federal Safe Drinking Water Act.
NOTE – If the manufacturer requests review to relevant alternate regulatory requirements, the certifying agency can consider alternative regulatory levels, e. g., Canadian Maximum Acceptable Concentrations (MACs).

2.14 normalization: The process of adjusting laboratory extraction results by accounting for differences between laboratory and field surface-area-to-volume ratios to reflect the contaminant concentration at the tap. 2.15 normalized concentration: A value for a contaminant concentration from a laboratory extraction test that has been adjusted to reflect the potential contaminant concentration at the tap. 2.16 point-of-entry system: A system with an inlet connection of 25.4 mm (1 in) or less that contacts all or a majority of the water entering the facility. 2.17 point-of-use system: A system located at a single tap or multiple taps that does not contact the majority of water entering the building or residence. 2.18 short-term exposure level (STEL): A maximum concentration of a contaminant that is permitted in drinking water for an acute exposure calculated in accordance with annex A of this Standard. 2.19 single product allowable concentration (SPAC): The maximum concentration of a contaminant in drinking water that a single product is allowed to contribute, as defined by annex A of this Standard.

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2.20 total allowable concentration (TAC): The maximum concentration of a nonregulated contaminant allowed in a public drinking water supply, as defined by annex A of this Standard. 2.21 transmission system: A system of conduits through which a primary water supply is transmitted to the distribution system.

3 General requirements
3.1 General 3.1.1 Product and material information described in 3.2 shall be used to determine the specific section (4 through 9) under which a product or material shall be evaluated. 3.1.2 Products or materials whose intended uses fall under more than one section of this Standard shall be evaluated under the section with the most rigorous evaluation conditions.
NOTE – Rigorous conditions are typically associated with shorter conditioning periods, longer exposure periods, higher surface-area-to-volume ratios, and higher exposure temperatures.

3.2 Information and formulation requirements The following information shall be reviewed to determine the appropriate analytical testing and to ensure that the potential health effects of products and materials are accurately and adequately identified: – the product section(s) under which the product, component, or material is covered and the intended function or end use of the product or the material; – for assembled products or components, a list of all of components and materials and their corresponding surface areas that come into direct contact with water; – – when appropriate, the total volume of water that the product can hold when filled to capacity; the expected service life of the product;

– the anticipated minimum, maximum, and average volumes of water that come into contact with the product, component, or material during a 24-h period; – complete formulation information for each water contact material as applicable’
NOTE – The complete formulation information may be omitted for a component material if the generic material type is contained in Table 3.1 and its diluted surface area in the application is less than or equal to 0.001 or 0.0001 for static or flowing conditions respectively.

– the composition of the formulation (e. g., percent or parts by weight for each chemical in the formulation or reference to a standardized material specification); – a chemical abstract number (CAS no.), name, trade designation, and supplier for each chemical present in the formulation and a Material Safety Data Sheet (MSDS), when available; and – an indication as to whether the chemical is an ingredient, reactant, or processing aid.

– the maximum temperature to which the product, component, or material is exposed during its intended end use;

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– a description/classification of the manner in which the product or material is manufactured (including any process parameters that affect product surface areas in direct contact with water), handled, and packaged. The manufacturing process variability shall be verified by the manufacturer as to its effect on contaminant leachate levels, and the manufacturer shall establish and demonstrate appropriate ongoing process controls to ensure ongoing product conformance with this Standard;
NOTE – The methods used to alter the water contact surfaces of product components during manufacturing, either mechanically (e. g., metal cutting, molding, stamping) or chemically (e. g., washing, coating, plating, brite-dip cleaning), may have a significant effect upon contaminant leachate performance.

– when available, a list of the known or suspected impurities within the product or material and the maximum percent or parts by weight of each impurity; – when available, the solubility, hydrolysis products, and extraction rates of chemicals within the product or material; and – when available, a list of published and unpublished toxicological studies relevant to the chemicals and impurities present in the product, component, or material. 3.3 Identification of analytes For all products and materials, the formulation information required in 3.2 shall be reviewed for completeness (e. g., all formulations total 100%), and to determine whether a minimum test battery has been established for each water contact material (see table 3.1). The availability of an established minimum test battery shall not preclude performance of a formulation review to identify any formulationdependent analytes (see 3.3.1). 3.3.1 Formulation-dependent analysis selection

For all water contact materials, the formulation information described in 3.2 shall be reviewed, and formulation-dependent analytes shall be identified for each water contact material. The criteria for selection of a formulation-dependent analyte shall include, but not be limited to, the following: – – – known or suspected toxicity of the substance or its byproduct(s); high water solubility of the substance; monomer(s) of polymeric ingredients;

– high probability of extraction of a substance or its byproduct(s) at toxicologically significant concentrations; and – 3.3.2 extraction or migration information for the substance provided by the manufacturer.

Established minimum test batteries

The materials listed in table 3.1 shall be tested for the indicated analyses and any formulation-dependent analyses identified during the formulation-dependent analyte selection. Products, components, or materials shall not require testing if their diluted surface area in the application is less than or equal to 0.001 or 0.0001 for static or flowing conditions respectively.

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Products manufactured entirely from annex C materials shall not be required to undergo extraction testing for material-specific analytes of interest. However, extraction testing for contaminants contributed by processes specific to a production site shall be considered formulation-dependent analytes. Annex C contains the evaluation requirements for qualification as an acceptable material.

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? 2007 NSF Table 3.1 – Material-specific analyses Material type Pipe/fitting/device materials asphaltic-coated ductile iron brass concrete copper galvanized steel stainless steel Plastic materials acetal (AC)/polyoxymethylene (POM) acrylonitrile-butadiene-styrene (ABS) cross linked polyethylene (PEX) nylon 6 other nylons polybutylene (PB) polyethylene (PE) polyphenylene oxide (PPO) polyphthalamide (PPA) polypropylene (PP) polysulphone including poly[phenylene sulphone] (PPSU) polyurethane (PUR) polyvinyl chloride (PVC) and chlorinated polyvinyl chloride (CPVC) polyvinyl chloride (flexible) Elastomer materials ethylene-propylene-diene monomer (EPDM) fluoroelastomer isoprene neoprene nitrile-butadiene rubber (NBR, BUNA-N) styrene-butadiene rubber Required analyses

NSF/ANSI 61 – 2007

GC/MS base/neutral scan (specific for carbonyls and non-aromatic hydrocarbons)1, volatile organic chemicals (VOCs), polynuclear aromatic hydrocarbons (PNAs), regulated metals2, molybdenum, vanadium, manganese regulated metals2, zinc, nickel regulated metals2 regulated metals2 regulated metals2, zinc, nickel regulated metals2, nickel formaldehyde, VOCs, regulated metals2, phenolics (by GC/MS base/acid scan)1, acetal oligomers (by GC/MS base/acid scan)1 acrylonitrile, 1,3-butadiene, styrene, regulated metals2, VOCs, phenolics (by GC/MS base/acid scan)1 GC/MS1, VOCs, regulated metals2, phenolics (by GC/MS base/acid scan)1, methanol, tert-butyl alcohol3 caprolactam, nitrogen-containing extractants (by GC/MS base/neutral scan)1, VOCs, regulated metals2, phenolics (by GC/MS base/acid scan)1 nitrogen-containing extractants (by GC/MS base/neutral scan)1, VOCs, regulated metals2, phenolics (by GC/MS base/acid scan)1, nylon monomers VOCs, regulated metals2, phenolics (by GC/MS base/acid scan)1 VOCs, regulated metals2, phenolics (by GC/MS base/acid scan)1 dimethyl phenol, VOCs, regulated metals2, phenolics (by GC/MS base/acid scan)1 hexamethylene diamine, terephthalic acid, isophthalic acid, VOCs, regulated metals2, phenolics (by GC/MS base/acid scan)1 VOCs, regulated metals2, phenolics (by GC/MS base/acid scan)1 sulphone monomer, VOCs, regulated metals2, phenolics (by GC/MS base/acid scan)1 GC/MS1, VOCs, regulated metals2, phenolics (by GC/MS base/acid scan)1 regulated metals2, phenolics1, VOCs, tin4, antimony5, residual vinyl chloride monomer (RVCM)6 VOCs, regulated metals2, phenolics (by GC/MS base/acid scan)1, phthalates7, RVCM6, tin4, zinc8 GC/MS1, VOCs, phenolics (by GC/MS PNAs1 GC/MS1, VOCs, phthalates7 GC/MS1, VOCs, phenolics (by GC/MS PNAs1, isoprene monomer GC/MS1, VOCs, phenolics (by GC/MS PNAs1, chloroprene GC/MS1, VOCs, phenolics (by GC/MS PNAs1, 1,3-butadiene, acrylonitrile GC/MS1, VOCs, phenolics (by GC/MS base/acid scan)1, phthalates7, base/acid scan)1, phthalates7, base/acid scan)1, phthalates7, base/acid scan)1, phthalates7, base/acid scan)1, phthalates7,

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? 2007 NSF Table 3.1 – Material-specific analyses Material type (SBR) Barrier materials asphaltic coatings epoxy coatings (liquid and powder) polyester coatings polyurethane coatings Portland and hydraulic cements
1
2 3 4 5

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Required analyses PNAs , 1,3-butadiene, styrene
1

regulated metals2, molybdenum, vanadium, manganese, VOCs, GC/MS base/neutral scan (specific for carbonyls and non-aromatic hydrocarbons)1, PNAs1 GC/MS (base/neutral/acid scan), bisphenol A, bisphenol A-diglycidyl ether9, bisphenol A-diglycideryl ether9, bisphenol A-propoxylate9, epichlorohydrin, VOCs, solvent and reactive diluent additives10 GC/MS (base/neutral/acid scan), VOCs, residual monomers11 GC/MS (base/neutral/acid scan), VOCs GC/MS1, regulated metals2, dioxins and furans, radionuclides, glycols and ethanolamines12

see annex B, section B.7 antimony, arsenic, barium, beryllium, cadmium, chromium, copper, lead, mercury, selenium, thallium tert-Butyl alcohol analysis is required for PEX materials except those crosslinked via e-beam methodology. The analysis for tin is required when tin-based stabilizers are used. The analysis for antimony is required when antimony-based stabilizers are used.

6 The level of RVCM within the walls of PVC or CPVC products and materials shall be directly determined (annex B, section B.7). 7

The analysis for phthalates is required when phthalate ester plasticizers are used. Analysis shall be for the specific phthalate ester(s) used in the formulation. The analysis for zinc is required when zinc-based stablilizers are used. Analysis shall be performed using liquid chromatography with ultraviolet detection (LC/UV).

8 9

Analysis shall be performed for the specific solvent and reactive diluent additives used in the individual product formulation, such as benzyl alcohol.
11

10

Analysis shall be performed for residual concentrations of the specific ester monomers used in the individual product formulation. Glycol and ethanolamine analyses shall be performed on cements containing these compounds as grinding aids.

12

– concluded –

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4 Pipes and related products
4.1 Scope 4.1.1 The requirements in this section apply to pipes and pipe-related products and the water-contact materials associated with these products. Pipe-related products include, but are not limited to, the following items: fittings, couplings, flexible and rigid tubing, riser tubing, dip tubes, hoses, well casings, drop pipes, screens, and pipe-related coatings. 4.1.2 Coatings and other barrier materials not exclusively intended for application to pipes or piperelated products are evaluated under 5.
NOTE – Coatings and other barrier materials that meet the requirements of 5 at a specific surface-area-tovolume ratio shall be considered to meet the requirements of a pipe or pipe-related product application for a surface-area-to-volume ratio less than or equal to the ratio accepted under the 5 evaluation.

4.1.3 Individual ingredients of cement-based pipes and related products (including Portland and blended hydraulic cement and admixtures) are evaluated under 5. 4.1.4 Products and materials intended to join or seal pipes or pipe-related products are evaluated under 6. 4.2 Definitions 4.2.1 cold water application: A product application that is intended to result in continuous exposure to water of ambient temperature. Products are tested for an end-use temperature of 23 ± 2 °C (73 ± 4 °F). 4.2.2 commercial hot water application: A product application that is intended to result in continuous or intermittent exposure to water that has been raised from ambient temperature. Intermittent exposure is defined as any hot water contact that is not continuous. Products are tested for an end-use temperature of 82 ± 2 °C (180 ± 3 °F). 4.2.3 domestic hot water application: A product application that is intended to result in continuous or intermittent exposure to water that has been raised from ambient temperature. Intermittent exposure is defined as any hot water contact that is not continuous. Products are tested for an end-use temperature of 60 ± 2 °C (140 ± 3 °F). 4.2.4 nominal diameter: A designation system used to specify a pipe size, where the designation for a specific size is approximately equal to the average inside diameter of the pipe. 4.3 General requirements 4.3.1 The product size with the most conservative normalization condition shall be evaluated. Successful evaluation of such a product shall qualify all products of less conservative normalization conditions, provided that the materials of construction are identical as specified in 4.4.1.
NOTE – For products of 1.3 to 10 cm (0.5 to 4 in) nominal diameter and products of 10 cm (4 in) diameter and greater, the most stringent normalization condition is typically the smallest inner diameter product within the nominal diameter range. Products of less than 1.3 cm (0.5 in) nominal diameter are assumed to have limited exposure in the distribution system (see assumptions in tables 4.4 and 4.5). Successful qualification of products of less than 1.3 cm (0.5 in) nominal diameter may not demonstrate the acceptability of all products 1.3 cm (0.5 in) nominal diameter and greater.

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Polyvinyl chloride and chlorinated polyvinyl chloride products and materials shall be evaluated for the level of residual vinyl chloride monomer (RVCM) in the product wall or in the material according to annex B, section B.7. 4.4 Sample requirements 4.4.1 General

A sample can represent a product line of various sizes when: – – – – 4.4.2 materials are of the same alloy, composition, or formulation; materials have undergone the same manufacturing process, e. g., casting or extrusion; designs and manufacturing processes are analogous; and/or it has the most stringent normalization requirements (see 4.3.1).

Materials

When a material is proposed for evaluation, a representative sample of the material shall be used. Material test samples (e. g., plaque or sheet) shall be used only if no chemical or physical difference exists between the material sample and the material as it is used in applications covered by 4. A material intended to be processed by more than one method (e. g., injection molding, extrusion, or stamping) shall be tested in each of its processed forms. 4.4.3 Finished products

When a finished product (e. g., pipe or fitting) is proposed for evaluation, a sample of the finished product shall be used for testing except in the following specific instances: – concrete cylinders, cubes, or other concrete surrogate samples can be evaluated on behalf of concrete-lined pipes and other concrete-based products; – coatings, applied to the appropriate substrate, can be evaluated on behalf of products whose entire water contact surface is covered by the coating; or – finished products shall be permitted to be evaluated using material samples if a finished product evaluation is impractical for one or more of the following reasons: – – – an internal volume greater than 20 L (5.3 gal); a weight greater than 34 kg (75 lb); or in situ manufacture of the finished product.

Material samples shall be permitted to be evaluated on behalf of a finished product if the first and second criteria listed under 4.4.1 are satisfied. 4.5 Extraction procedures 4.5.1 Analytical summary

An analytical summary shall be prepared for each product or material. The analytical summary shall consist of the formulation-dependent analytes identified in 3.2 and the applicable material-specific analytes listed in table 3.1.

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4.5.2.1 In all cases, test samples shall be prepared so that the laboratory surface-area-to-volume ratio is equal to or greater than the surface-area-to-volume ratio at which the product is intended to be used in the field.
NOTE – To facilitate the exposure of product samples that are connected to pipe or tubing products under normal installation conditions (e. g., fittings), the samples may be attached to lengths of pipe or tubing of the appropriate nominal diameter. When a test sample is prepared in this manner, the exposed surface area of the fitting test sample shall represent a percentage of the total exposed surface area (test sample plus the attached pipe or tubing) that is equal to or greater than the percentage specified in the table 4.5 normalization assumptions, for the specific nominal diameter and end use of the product (flexible or rigid piping system). The pipe or tubing material shall also be present in the method blank as required in annex B, section B.2.8.1.

4.5.2.2 Unless the manufacturer’s instructions direct otherwise, test samples shall be rinsed in cold tap water until any extraneous debris or contamination that occurred during shipping and handling is removed. The samples shall then be rinsed in reagent water that meets the requirements of annex B, section B.9.2.1 4.5.2.3 If the exterior surface of a product is to be exposed, all markings that are not integral to the product (e. g., ink markings) shall be removed. 4.5.2.4 When the test sample contains internal threaded outlets, 75% of the threaded surface area shall be covered by insertion of a threaded component of the appropriate diameter to produce a watertight seal. 4.5.3 Exposure water

4.5.3.1 General Exposure water selection shall be determined by the analytes of interest identified on the analytical summary (see 4.5.1). Exposure water(s) shall be selected in accordance with annex B, section B.2.5. 4.5.3.2 Copper and copper alloys Copper and copper alloy pipe and tubing shall be exposed in the pH 6.5 and pH 10 exposure waters as described in annex B, section B.9. Copper and copper alloy fittings intended to be used with copper pipe and tubing shall be exposed in either the pH 5 or the pH 6.5 exposure waters (at the discretion of the manufacturer) and in the pH 10 exposure water, as described in annex B, section B.9. For all copper and copper alloy pipes, tubing, and fittings tested using the pH 6.5 exposure water, the manufacturer’s literature shall indicate this use limitation by inclusion of the following statement in the use instructions or product literature that references this Standard: “Copper [tube, pipe, or fitting] (Alloy [alloy designation]) has been evaluated by [Testing Organization] to NSF/ANSI 61 for use in drinking water supplies of pH 6.5 and above. Drinking water supplies that are less than pH 6.5 may require corrosion control to limit leaching of copper into the drinking water.” 4.5.4 Conditioning and exposure options

4.5.4.1 In-product conditioning and exposure During in-product conditioning and exposure, the test sample shall be filled completely with exposure water. The product with the greatest surface-area-to-volume ratio (typically the smallest diameter) shall be preferentially used. Samples shall be capped with inert materials (e. g., glass) when capping is necessary to prevent the loss of exposure water.

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4.5.4.2 In-vessel conditioning and exposure During in-vessel conditioning and exposure, samples shall be placed in containers that are composed of a material that is inert to the exposure water and that have polytetrafluoroethylene lined lids. The exposure water shall completely immerse the sample. All samples shall be exposed at a surface-area-tovolume ratio that is equal to or greater than that of the intended end use. The actual wetted surface-areato-volume ratio achieved during the exposure shall be recorded.
NOTE – The stated duration of the conditioning period at the hot temperature does not include any time needed to elevate the product sample or exposure vessel to the required exposure temperature.

4.5.4.3 Multiple time point protocol When the normalized concentration of a contaminant exceeds, or is expected to exceed, its acceptable level when evaluated as a single time point exposure (see 4.5.6), determination of the contaminant leaching rate as a multiple time point exposure shall be considered (see 4.5.7). For the purpose of contaminant concentration evaluation (see 4.8.2), Day 1 shall be defined as the time point at which extractant water is collected for analysis under the single time point exposure protocol in table 4.2 (17 d in elapsed time). Day 90 shall be defined as 90 d after this time point.
NOTE – When a multiple time point protocol is employed for the evaluation of a contaminant, consideration shall be given to the leaching characteristics of the contaminant, e. g., whether the leaching pattern demonstrates a linear regression. Consideration shall also be given to the availability of appropriate toxicity data to define an acute exposure limit for the contaminant, as required in 4.8.2.

4.5.5

Single time point conditioning protocols

A separate sample shall be conditioned for each type of exposure water selected in 4.5.3. 4.5.5.1 Single time point conditioning – cold application Products that are intended to be in contact with only cold water shall be conditioned in the exposure water(s) selected in 4.5.3 at 23 ± 2 °C (73 ± 4 °F) for 14 d. During the 14-d period, the exposure water shall be changed at least 10 times with a minimum period of 24 ± 1 h between water changes. The free available chlorine concentration during the conditioning period shall be 2 mg/L. After the 14-d conditioning period, the exposure water in the product or in the vessel shall be decanted and discarded. Shortened conditioning periods shall be permitted at the request of the manufacturer. Exposure of the sample according to 4.5.6 shall immediately follow conditioning.
NOTE – Table 4.1 provides an example single time point conditioning protocol. Alternate protocols shall be permitted as long as the requirements of 4.5.5.1 are met.

4.5.5.2 Single time point conditioning – hot applications 4.5.5.2.1 Intermittent hot water conditioning

Products that are intended to be in intermittent contact with hot water shall undergo the cold application conditioning according to 4.5.5.1. At the conclusion of the cold application conditioning, the products shall be further conditioned in the exposure water(s) selected in 4.5.3 at either 60 ± 2 °C (140 ± 3 °F) or 82 ± 2 °C (180 ± 3 °F) for two consecutive 60 ± 5 min periods. The exposure water shall be decanted and discarded after each 1-h period. Exposure of the sample according to 4.5.6 shall immediately follow completion of the further conditioning.
NOTE – The stated duration of the conditioning period at the hot temperature does not include any time needed to elevate the product sample or exposure vessel to the required exposure temperature.

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Products that are intended to be in continuous contact with hot water shall be conditioned in the exposure water(s) selected in 4.5.3 at either 60 ± 2 °C (140 ± 3 °F) or 82 ± 2 °C (180 ± 3 °F) for 14 d. During the 14-d period, the exposure water shall be changed at least 10 times with a minimum period of 24 ± 1 h between water changes. The free available chlorine concentration during the conditioning period shall be 2 mg/L. After the 14-d conditioning period, the exposure water in the product or in the vessel shall be decanted and discarded. Shortened conditioning periods shall be permitted at the request of the manufacturer. Exposure of the sample according to 4.5.6 shall immediately follow conditioning.
NOTE – Table 4.1 provides an example single time point conditioning protocol. Alternate protocols shall be permitted as long as the requirements of 4.5.5.2 are met.

4.5.6

Single time point exposure protocols

Products to be evaluated at a single time point shall be exposed according to the schedule in table 4.2. The first two 24-h exposure periods shall be optional at the discretion of the manufacturer. A separate sample shall be exposed for each type of exposure water selected in 4.5.3. For each sample, the exposure water shall be of the same pH as the water used for conditioning of the sample. 4.5.6.1 Single time point exposure – cold application Immediately after conditioning, the product shall be exposed at 23 ± 1 °C (73 ± 2 °F) according to the schedule in table 4.2. 4.5.6.2 Single time point exposure – hot applications 4.5.6.2.1 Intermittent hot water exposure

Immediately after conditioning, the product shall undergo the cold application exposure according to 4.5.6.1. Prior to the final 16-h exposure, the product shall be exposed at the selected elevated temperature, either 60 ± 1 °C (140 ± 2 °F) or 82 ± 1 °C (180 ± 2 °F), for 30 ± 5 min. The product shall then be exposed at 23 ± 1 °C (73 ± 2 °F) for the duration of the exposure period. The exposure water shall not be decanted prior to initiation of the final 16-h exposure. 4.5.6.2.2 Continuous hot water exposure

Immediately after conditioning, the product (in-product exposures) or the exposure vessel (in-vessel exposures) shall be filled with fresh exposure water of the applicable pH (see 4.5.3). The product shall then be exposed at the selected elevated temperature, either 60 ± 1 °C (140 ± 2 °F) or 82 ± 1 °C (180 ± 2 °F), according to the schedule in table 4.2. 4.5.7 Multiple time point conditioning/exposure protocols

For the purpose of determining a contaminant leaching rate as a function of time, extractant water samples shall be collected during the conditioning period of products for which multiple time point exposure has been elected, according to the protocols in 4.5.7.1 and 4.5.7.2. A separate sample shall be conditioned and exposed for each type of exposure water selected in 4.5.3. 4.5.7.1 Cold application Products that are intended to be in contact with only cold water shall be maintained at 23 ± 1 °C (73 ± 2 °F) for 19 d. During the 19-d period, the exposure water shall be changed at least 12 times, with a minimum period of 24 ± 1 h between water changes. At seven of these water changes, extraction water shall be collected for analysis after a 24-h exposure. For extrapolation and normalization purposes, the number of hours elapsed since the most recent water change (or sample collection) and the number of

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days elapsed since the initiation of the exposure shall be recorded at the time of each extraction water collection.
NOTE – Table 4.3 provides an example multiple time point conditioning/exposure protocol. Alternate protocols shall be permitted as long as the requirements of 4.5.7.1 are met.

At the discretion of the manufacturer, direct measurement of a Day 90 extraction shall be permitted. The products shall be maintained at 23 ± 1 °C (73 ± 2 °F). Extraction water shall be collected for analysis at a minimum of two time points: after Day 1 (representing 14 d of conditioning and 1 d of acute exposure), and after the final exposure terminating on Day 90 (representing 14 d of conditioning, 1 d of acute exposure, and 90 d of chronic exposure). The exposure water shall be changed at least 4 d per week during the interval between the initial and final exposures. Exposures that are used for the collection of extractant water for analysis shall not exceed 24 ± 1 h in duration. 4.5.7.2 Hot applications 4.5.7.2.1 Intermittent hot water exposure

Products that are intended to be in intermittent contact with hot water shall undergo the cold application exposure according to 4.5.7.1. At the initiation of each exposure that will be collected for analysis, the product shall be exposed at the selected elevated temperature, either 60 ± 1 °C (140 ± 2 °F) or 82 ± 1 °C (180 ± 2 °F), for 30 ± 5 min. The product shall then be exposed at 23 ± 1 °C (73 ± 2 °F) for the duration of the exposure period. The exposure water shall not be decanted prior to the completion of the exposure period.
NOTE 1 – Table 4.3 provides an example multiple time point conditioning/exposure protocol. Alternate protocols shall be permitted as long as the requirements of 4.5.7.2.1 are met. NOTE 2 – The stated duration of the conditioning period at the hot temperature does not include any time needed to elevate the product sample or exposure vessel to the required exposure temperature.

At the discretion of the manufacturer, direct measurement of a Day 90 extraction shall be permitted. At the initiation of each exposure that will be collected for analysis, the products shall be exposed at the selected elevated temperature, either 60 ± 1 °C (140 ± 2 °F) or 82 ± 1 °C (180 ± 2 °F), for 30 ± 5 min. The product shall then be exposed at 23 ± 1 °C (73 ± 2 °F) for the duration of the exposure period. The exposure water shall not be decanted prior to the completion of the exposure period. Extraction water shall be collected for analysis at a minimum of two time points: after Day 1 (representing 14 d of conditioning and 1 d of acute exposure), and after the final exposure terminating on Day 90 (representing 14 d of conditioning, 1 d of acute exposure, and 90 d of chronic exposure). The exposure water shall be changed at least 4 d per week during the interval between the initial and final exposures. Exposures that are used for the collection of extractant water for analysis shall not exceed 24 ± 1 h in duration. 4.5.7.2.2 Continuous hot water exposure

Products that are intended to be in continuous contact with hot water shall be maintained at the selected elevated temperature, either 60 ± 1 °C (140 ± 2 °F) or 82 ± 1 °C (180 ± 2 °F) for 19 d. During the 19-d period, the exposure water shall be changed at least 12 times with a minimum period of 24 ± 1 h between water changes. At seven of these water changes, extraction water shall be collected for analysis after a 24-h exposure. For extrapolation and normalization purposes, the number of hours elapsed since the most recent water change (or sample collection) and the number of days elapsed since the initiation of the exposure shall be recorded at the time of each extraction water collection.
NOTE – Table 4.3 provides an example multiple time point conditioning/exposure protocol. Alternate protocols shall be permitted as long as the requirements of 4.5.7.2.2 are met.

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At the discretion of the manufacturer, direct measurement of a Day 90 extraction shall be permitted. The products shall be maintained at the selected elevated temperature, either 60 ± 1 °C (140 ± 2 °F) or 82 ± 1 °C (180 ± 2 °F). Extraction water shall be collected for analysis at at least two time points: after Day 1 (representing 14 d of conditioning and 1 d of acute exposure), and after the final exposure terminating on Day 90 (representing 14 d of conditioning, 1 d of acute exposure, and 90 d of chronic exposure). The exposure water shall be changed at least 4 d per week during the interval between the initial and final exposures. Exposures that are used for the collection of extractant water for analysis shall not exceed 24 ± 1 h in duration. 4.5.8 Collection and preservation of extraction water

Immediately after exposure, extraction waters collected for analysis shall be poured into previously prepared sample containers for storage until analysis, as specified in annex B, section B.6. 4.6 Analysis 4.6.1 Extraction waters shall be analyzed with the methods listed in annex B, section B.7.

4.6.2 Samples requiring analysis for residual vinyl chloride monomer shall be evaluated according to the method in annex B, section B.7. 4.7 Normalization of contaminant concentrations 4.7.1 General

The concentration of analytes detected in the extraction water shall be multiplied by a calculated normalization factor (NF) to account for differences between laboratory and field surface-area-to-volume ratios. The normalization factor shall be based on calculations and assumptions relevant to the end use of the product. The general formula for the derivation of the normalization factor is described in the following equations: NF N1 N2 where: SAF = surface area exposed in the field; SAL = surface area exposed in the laboratory; VL = volume of extraction water used in the laboratory; VF(static) = volume of water to which the product is exposed under static conditions; and VF(flowing) = volume of water to which the product is exposed under flowing conditions during a period of time equivalent to the laboratory test. When the length of the exposure being normalized is other than 16 h in length, the normalized value shall be adjusted to reflect a 16-h exposure (e. g., multiply the normalized value by 0.7 when a 24-h exposure = = = N1 x N2 SAF SAL VF(static) VF(flowing) x VL VF(static)

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was used). The nominal diameter of the product shall determine which assumptions are used for normalization (see tables 4.4 and 4.5). The actual inner diameter of the product shall be used for the normalization calculations of surface area and volume.
NOTE – Adjustment of the normalized contaminant concentration for the duration of the exposure period shall consider the extraction kinetics of the contaminant under evaluation. For contaminants that do not exhibit linear extraction kinetics, adjustment for the duration of exposure shall be done in accordance with the demonstrated kinetics of the contaminant or shall not be applied if this information is not available.

4.7.2

Products installed at regularly repeating intervals

For products installed at regularly repeating intervals (e. g., pipes, fittings), the SAF shall be calculated from the assumed length of pipe corresponding to the segment of the system in which the product is used (e. g., 100 ft of pipe in the service line or 280 ft of pipe in the residence). The VF(static) component of the N1 term shall be the volume of water contained within the assumed length of pipe. For fittings, the actual inner diameter of the pipe used with the fittings shall be used to calculate both SAF and VF(static). 4.7.3 Products not installed at regularly repeating intervals

Products not installed at regularly repeating intervals shall be identified through review of the manufacturer’s recommended product end use. For products not installed at regularly repeating intervals (e. g., transition fittings, repair couplings, drop ear elbow fittings, and copper stub outs), the SAF shall be the wetted surface area of a single product. The VF(static) component of the N1 term shall be the volume of water a single product contains when filled to capacity, except that VF(static) shall equal 1 L (0.26 gal) for all products that contain less than 1 L (0.26 gal) of water when filled to capacity. 4.7.4 4.7.5 Sample calculations for normalization of products in 4 are provided in table 4.6. Selection of normalization conditions

Pipe and fitting products with a nominal diameter greater than or equal to 10 cm (4 in) shall be normalized to the flowing condition. Pipe and fitting products with a nominal diameter of less than 10 cm (4 in) shall be normalized to the static condition when the value of N2 is less than or equal to 0.1. Pipe and fitting products with a nominal diameter of less than 10 cm (4 in) shall be normalized to the flowing condition when the value of N2 is greater than 0.1. 4.7.6 Multiple time point exposure calculations

Laboratory values from each time point at which extractant water was collected (a minimum of five data points shall be required for extrapolation) shall be normalized as indicated in 4.7.1, depending on product end use. A decay curve of these normalized contaminant concentrations in relation to elapsed exposure time shall be plotted. Contaminant concentrations shall be determined for two time points as follows: at Day 1 (representing 14 d of conditioning and 1 d of acute exposure) and at Day 90 (representing 14 d of conditioning, 1 d of acute exposure, and 90 d of chronic exposure) shall be extrapolated from this curve (see 4.5.7). If direct measurement of a Day 90 exposure has been performed, laboratory values from each time point at which extractant water was collected (a minimum of two time points as defined in 4.5.7.1 and 4.5.7.2) shall be normalized as indicated in 4.7.1, depending on product end use.

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? 2007 NSF 4.8 Evaluation of contaminant concentrations 4.8.1 Contaminants measured in a single time point extraction

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For pipe and fitting products, normalized static contaminant concentrations shall be no greater than their respective MCLs or TACs, and normalized flowing contaminant concentrations shall be no greater than their respective SPACs calculated in accordance with annex A. 4.8.2 Contaminants measured in a multiple time point extraction

Normalized Day 1 contaminant concentrations shall not exceed the short-term exposure level (STEL) as defined in annex A, section A.5. Normalized extrapolated or directly measured Day 90 contaminant concentrations shall not exceed the limits defined in 4.8.1. 4.8.3 Residual vinyl chloride monomer (RVCM)

The average RVCM concentration shall be less than or equal to 3.2 mg/kg as evaluated in the product wall. Table 4.1 – Example single time point conditioning schedule Conditioning time 24 ± 1 h 24 ± 1 h 24 ± 1 h 24 ± 1 h 72 ± 1 h 24 ± 1 h 24 ± 1 h 24 ± 1 h 24 ± 1 h 72 ± 1 h Elapsed time 1d 2d 3d 4d 7d 8d 9d 10 d 11 d 14 d Comment Exposure water is decanted and discarded; the exposure vessel or product is refilled with exposure water and conditioning is continued. Exposure water is decanted and discarded; the exposure vessel or product is refilled with exposure water and conditioning is continued. Exposure water is decanted and discarded; the exposure vessel or product is refilled with exposure water and conditioning is continued. Exposure water is decanted and discarded; the exposure vessel or product is refilled with exposure water and conditioning is continued. Exposure water is decanted and discarded; the exposure vessel or product is refilled with exposure water and conditioning is continued. Exposure water is decanted and discarded; the exposure vessel or product is refilled with exposure water and conditioning is continued. Exposure water is decanted and discarded; the exposure vessel or product is refilled with exposure water and conditioning is continued. Exposure water is decanted and discarded; the exposure vessel or product is refilled with exposure water and conditioning is continued. Exposure water is decanted and discarded; the exposure vessel or product is refilled with exposure water and conditioning is continued. Exposure water is decanted and discarded; conditioning is terminated.

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? 2007 NSF Table 4.2 – Single time point exposure schedule Exposure time 24 ± 1 h (optional) 24 ± 1 h (optional) Elapsed time1 15 d (optional) 16 d (optional) 17 d (15 d if the two optional exposure periods are not elected)

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Comment Extraction water is decanted and discarded; the exposure vessel or product is refilled with exposure water and exposure is continued. Extraction water is decanted and discarded; the exposure vessel or product is refilled with exposure water and exposure is continued. Extraction water is collected for analysis.

16 h
1

Elapsed time indicated includes the 14 d of conditioning preceding the exposure.

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NSF/ANSI 61 – 2007 Table 4.3 – Example multiple time point conditioning/exposure schedule

Exposure time 24 ± 1 h

Elapsed time 1d

24 ± 1 h

2d

24 ± 1 h

3d

24 ± 1 h

4d

72 ± 1 h

7d

24 ± 1 h

8d

24 ± 1 h

9d

24 ± 1 h

10 d

96 ± 1 h

14 d

24 ± 1 h

15 d

72 ± 1 h 24 ± 1 h

18 d 19 d

Sample collection Extraction water is collected for analysis at completion of the exposure period; the product or exposure vessel is refilled with exposure water and the exposure is continued. Extraction water is collected for analysis at completion of the exposure period; the product or exposure vessel is refilled with exposure water and the exposure is continued. Extraction water is decanted and discarded; the product or exposure vessel is refilled with exposure water and the exposure is continued. Extraction water is collected for analysis at completion of the exposure period; the product or exposure vessel is refilled with exposure water and the exposure is continued. Extraction water is decanted and discarded; the product or exposure vessel is refilled with exposure water and the exposure is continued. Extraction water is collected for analysis at completion of the exposure period; the product or exposure vessel is refilled with exposure water and the exposure is continued. Extraction water is decanted and discarded; the product or exposure vessel is refilled with exposure water and the exposure is continued. Extraction water is collected for analysis at completion of the exposure period; the product or exposure vessel is refilled with exposure water and the exposure is continued. Extraction water is decanted and discarded; the product or exposure vessel is refilled with exposure water and the exposure is continued. Extraction water is collected for analysis at completion of the exposure period; the product or exposure vessel is refilled with exposure water and the exposure is continued. Extraction water is decanted and discarded; the product or exposure vessel is refilled with exposure water and the exposure is continued. Extraction water is collected for analysis at completion of the exposure period; the exposure is terminated.

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Table 4.4 – Pipes – normalization factors and assumptions Product nominal diameter non-copper pipe nominal ≥ 10 cm (4 in) Assumptions – water is exposed to the same material from the treatment plant to the service line – a 16-h exposure period is evaluated – a 16-h exposure period is evaluated in-product 10 cm (4 in) > nominal ≥ 1.3 cm (0.5 in) – residential water usage is 681 L (180 gal) per 24 h – 100 ft of service line from water main to residence – a maximum run of 7.6 m (25 ft) of small diameter product is installed – for products with an internal volume less than 1 L (0.26 gal), VF(static) is set equal to 1 L – a 16-h exposure period is evaluated – residential water usage is 681 L (180 gal) per 24 h – 280 ft per residence (140 ft each for hot and cold sides) – utilized as main distribution lines within buildings1 in-vessel calculated according to 4.7.1 calculated according to 4.7.1 in-vessel calculated according to 4.7.1 Exposure type in-product N1 1 calculated according to 4.7.1 N2 (flowing condition) 1

in-vessel

1

1

calculated according to 4.7.1 calculated according to 4.7.1

in-product

1

calculated according to 4.7.1

nominal < 1.3 cm (0.5 in)

in-product in-vessel

1 calculated according to 4.7.1

0.55

0.55 – a 16-h exposure period is evaluated 1 The N2 value for copper products used as main distribution lines in buildings was calculated based on the static volume of a piping network of up to 20 mi and an average flow of 100 gpm.

copper pipe ≥ 10 cm (4 in)

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Table 4.5 – Fittings (installed at regular intervals) – normalization factors and assumptions Product nominal diameter Exposure type N2 (flowing condition) 1

Assumptions

N1 0.02

Nominal ≥ 10 cm (4 in)

– water is exposed to the same material in-product from the treatment plant to the service line – fittings represent 2% of the distribution system surface area

10 cm (4 in) > nominal > 1.3 cm (0.5 in)

calculated according to in-vessel 4.7.1 and multiplied by – a 16-h exposure period is evaluated 0.02 – fittings represent 2% of the piping 0.02, 0.06, or system for products 10 cm (4 in) > 0.03 nominal ≥ 2.5 cm (1.0 in) (rigid and depending flexible systems) on product in-product diameter and – fittings represent 6% of the piping end use system surface area for products 2.5 cm (flexible or (1.0) in > nominal ≥ 1.3 cm (0.5 in) (rigid rigid system) systems)1 calculated – fittings represent 3% of the piping according to system surface area for products 2.5 cm 4.7.1 and (1.0) in > nominal ≥ 1.3 cm (0.5) in multiplied by (flexible systems)1 0.02, 0.06, or 0.03 in-vessel – a 16-h exposure period is evaluated depending on product – residential water usage is 681 L (180 diameter and gal) per 24 h end use (flexible or – 100 ft of service line from water main to rigid system) residence 0.06 or 0.03 – a maximum run of 7.6 m (25 ft) of small depending diameter product is installed on product end use – fittings represent 6% of the residential in-product (flexible or system surface area for rigid piping rigid system) systems1 calculated according to 4.7.1 and multiplied by 0.06 or 0.03 depending on product end use (flexible or rigid system)

1

calculated according to 4.7.1

calculated according to 4.7.1

calculated according to 4.7.1

– fittings represent 3% of the residential system surface area for flexible piping nominal < 1.3 cm systems1 (0.5 in) – a 16-h exposure period is evaluated – residential water usage is 681 L (180 gal) per 24 h – 280 ft of pipe per residence (140 ft) each for hot and cold sides) in-vessel

calculated according to 4.7.1

1 For products that may be used with either rigid or flexible systems, fittings shall be assumed to represent 6% of the piping system surface area.

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? 2007 NSF Table 4.6 – Example normalization calculations

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In-product exposure of a 30.5 cm (1 ft) length of 15.2 cm (6 in) i. d. pipe Parameters: normalized SAF = 1459 cm2 (226 in2) laboratory 1.5 gal 226 in2 x 1 x x flowing = SAL = 1459 cm2 (226 in2) 226 in2 1.5 gal concentration VF(static) = 5.6 L (1.5 gal) concentration VL = 5.6 L (1.5 gal) In-vessel exposure of a 2.5 cm (1 in) i. d. pipe Parameters: SAF/ VF(static) = 1575 cm2/1 L normalized laboratory 0.2 gal 924 in2 static x x (924 in2/1 gal) = concentration 247 in2 1 gal 2 2 concentration SAL= 247 in (1 594 cm ) VL = 0.2 gal (0.8 L) In-product exposure of a 63.5 cm (25 ft) length of 0.6 cm (0.25 in) i. d. pipe Parameters: SAF = 1520 cm2 (235.6 in2) normalized SAL = 1520 cm2 (235.6 in2) 235.6 in2 0.064 gal laboratory static = x x VF(static) = 0.24 L (0.064 gal) – 0.26 gal 235.6 in2 concentration concentration default to 1 L (0.26 gal) VL = 0.24 L (0.064 gal) In-product exposure of a 25.4 (10 in) long 15.2 (6 in) i. d. fitting Parameters: SAF = 1216.1 cm2 (188.5 in2) normalized laboratory 1.2 gal 188.5 in2 x 1 x 0.02 x SAL = 1216.1 cm2 (188.5 in2) flowing x = concentration 1.2 gal 188.5 in2 concentration VF(static) = 4.6 L (1.2 gal) VL = 4.6 L (1.2 gal) In-vessel exposure of a 1.3 cm (0.5 in) i. d. fitting used with flexible piping systems Parameters: SAF/ VF(static) = 3040 cm2/1 L normalized laboratory 0.2 gal 1885 in2 x 0.03 x x (1885 in2/1 gal) static = 247 in2 1 gal concentration concentration SAL = 1594 cm2 (247 in2) VL = 0.8 L (0.2 gal) In-vessel exposure of a 0.6 cm (0.25 in) i. d. fitting used with rigid piping systems Parameters: SAF / VF(static) = 908 in2/1 gal normalized (1523 cm2/1 L) 236 in2 0.4 gal laboratory = x x 0.06 x SAL = 865 in2 (5 581cm2) static 865 in2 0.26 gal concentration VF(static) = 0.064 gal (0.24 L) – concentration default to 0.26 gal (1 L) VL = 0.4 gal (1.3 L) In-vessel exposure of a 1.3 cm (0.5 in) i. d. fitting used as a repair coupling Parameters: SAF / VF(static) = 3040 cm2/1 L (1885 in2/1 gal) normalized laboratory 0.4 gal 1.6 in2 x x = VF(static) = 0.003 L (0.0009 gal) static concentration 865 in2 0.26 gal default to 1 L (0.26 gal) concentration 2 2 SAL = 5581cm (865 in ) VL = 1.3 L (0.4 gal)
NOTE – Definitions for SAF, SAL, VF(static),VF(flowing), and VL are found in 4.7.1.

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5 Barrier materials
5.1 Scope The requirements of this section apply to products and materials intended to form a barrier providing containment of drinking water or to prevent drinking water contact with another surface. The products and materials that are covered include, but are not limited to: non-residential storage tanks, coatings, paints, linings and liners, bladders, diaphragms, and constituents of concrete and cement-mortar (e. g., Portland and blended hydraulic cements, admixtures, sealers, and mold release agents). These products and materials can be field-applied, factory-applied, precast, or cast in place. 5.2 Definitions 5.2.1 admixture: A material other than water, aggregates, hydraulic cement, and fiber reinforcement used as an ingredient of concrete or mortar and added to the batch immediately before or during its mixing. 5.2.2 aggregate: Granular material, such as sand, gravel, or crushed stone, used with a cementing medium to form hydraulic-cement concrete or mortar. 5.2.3 barrier material: A material in contact with drinking water that serves a containment or separation purpose. 5.2.4 blended hydraulic cement: A hydraulic cement consisting of two or more inorganic constituents (at least one of which is not Portland cement or Portland cement clinker) that separately or in combination contribute to the strength-gaining properties of the cement. 5.2.5 coating/paint: A material applied to a surface where a direct bond to the substrate is formed.

5.2.6 concrete: A composite material that consists essentially of a binding medium within which are embedded particles or fragments of aggregate; in hydraulic-cement concrete, the binder is formed from a mixture of hydraulic cement and water. 5.2.7 diaphragm/bladder: A flexible membrane that separates the surrounding media from the drinking water. 5.2.8 form/mold release agent: A material applied to the inside of a form or mold used to cast concrete or cement-mortar, which prevents adhesion of the concrete or cement-mortar to its surface. 5.2.9 hydraulic cement: A cement that sets and hardens by chemical interaction with water and that is capable of doing so under water. 5.2.10 liners/linings: Prefabricated materials applied, bonded, or attached to a surface that is subject to direct/indirect contact with drinking water. 5.2.11 mortar: A mixture of water, cement, and sand. 5.2.12 Portland cement: A hydraulic cement (usually containing calcium sulfate) produced by pulverizing Portland cement clinker (a partially fused substance consisting primarily of hydraulic calcium silicates). 5.2.13 potable water contact area of tanks: The potable water contact areas of tanks shall include both the area normally submerged during use, and areas where water may condense and fall back into the tank, such as ceilings.

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5.2.14 sealer: A liquid that is applied as a coating to the surface of hardened concrete or cement-mortar, either to prevent or to decrease the penetration of liquid or gaseous media during service exposure. 5.3 General requirements 5.3.1 Product labeling

Products or product containers shall be marked and shall include, at a minimum, product identification, batch number, or date of manufacture. When it is not feasible to mark the product or material, the manufacturer shall maintain identification records. 5.3.2 Paints and coatings

For all paints and coatings, the manufacturer shall submit detailed use instructions. Use instructions shall specify the appropriate preparation and application procedures, including order of application for multiple layer systems, substrate preparation (including use of specific primer), subcomponent mixing, induction time, thinning, application method, application thickness(es), curing schedule, and final cure time prior to water immersion. Coating systems that are composed of multiple products (e. g., primer, intermediate coat/s, and top coat, including any thinners) shall be evaluated as applied systems. 5.4 Sample requirements When required for evaluation, a sample of the product or material equivalent to that used in field applications shall be obtained. A single sample can represent a product line of similar formulations (e. g., different colors of the same coating product line) when: – the sample selected for testing contains all the formulation ingredients of toxicological concern (see 3.2) at concentrations equal to or greater than the products it is selected to represent; and – product application conditions for the sample selected for testing (e. g., application thickness/es, cure times, solvent concentrations) are equal to or more severe than the products it is selected to represent; and – for multiple component formulations, the mixing ratio/s of the selected sample is/are identical to that of the products it represents. 5.4.1 Cement samples

Cement samples, weighing a minimum of 9 kg (20 lbs), shall be collected in accordance with the applicable sections of ASTM C 183. To minimize contamination, all sample collection tools shall be cleaned and wiped with isopropyl alcohol before use. Collected samples shall be placed in moisture-proof containers. To minimize organic contamination, sample containers shall not be filled near a running motor or any type of exhaust system. 5.4.2 Concrete cylinder samples

Concrete test cylinders for the evaluation of cast-in-place or precast concrete structures shall be submitted with specific information on the composition of the concrete mix design for the specific installation, including the specific sources of cement, aggregate, admixtures, and any other additives. Specific information on the tank dimensions and water storage capacity shall also be provided. Concrete

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batch tickets, collected at the site of production, shall serve as evidence of the concrete mix actually used in the structure being evaluated. 5.4.3 Other barrier materials

Samples of barrier materials shall be collected at the point of manufacture. 5.5 Extraction procedures 5.5.1 Analytical summary

An analytical summary shall be prepared for each product. The analytical summary shall consist of the formulation-dependent analytes identified through the formulation review (see 3.2) and the applicable material-specific analytes listed in table 3.1. 5.5.2 Preparation of test samples

5.5.2.1 In all cases, test samples shall be prepared so that a minimum surface-area-to-volume ratio of 50 cm2/L (29 in2/gal) is achieved during the exposure, and so that the entire surface to be exposed is covered by exposure water. Samples shall be rinsed with cold tap water and then in reagent water that meets the requirements of annex B, section B.9.2.1, unless the manufacturer’s instructions direct otherwise. 5.5.2.2 Field-applied paint and coating systems Field-applied paint & coating systems shall be applied in accordance with the manufacturer’s published use instructions (see 5.3.2) under the supervision of the testing laboratory. Products shall be applied to a glass slide when appropriate. Products requiring a reactive substrate shall be applied to the appropriate alternate substrate. Coating products shall be applied using application conditions as specified by the manufacturer in the product use instructions, e. g., the highest recommended percentage of thinner, the shortest curing period between coats or layers, the maximum recommended film thickness per coat, and the shortest final curing period prior to immersion. For exothermic coatings with a maximum field use thickness in excess of 120 mil (3.0 mm), an additional evaluation at the manufacturer’s minimum recommended field use thickness shall be conducted. The maximum dry film thickness per coat attested to by the testing laboratory shall be based on the average per coat dry film thickness evaluated.
NOTE – The practical application of coatings may result in spots of coating thicknesses in excess of the maximum dry film thickness per coat attested to by the testing laboratory. Acceptable variations from the maximum dry film thicknesses can occur. The average of spot measurements on each 10 m2 (100 ft2) area shall not exceed the specified maximum thickness, and no single spot measurement shall be more than 120% of it. Spot measurements are defined as the average of at least three gauge readings within a 1.5 in (4 cm) diameter circle.

Multiple layer paint and coating systems that require the application of distinct coating product formulations in sequence shall be applied in a stepped manner so as to expose all layers. Multiple coats of the same product (of the same color) applied in sequence shall not constitute multiple layers and shall not be applied in a stepped manner. Multiple coats of the same product (of different colors) applied in sequence shall not constitute multiple layers and shall not be applied in a stepped manner, unless deemed necessary by the testing laboratory to address potential health effects concerns from the differences in color formulations. Stepped coating systems shall be applied per the dimensions in table 5.1. 5.5.2.3 Factory-applied or cured systems Paint and coating systems requiring factory application, factory curing, or both shall be prepared in accordance with the manufacturer’s published use instructions under the supervision of the testing laboratory. These products shall be applied in accordance with the manufacturer’s published use instructions (see

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5.3.2). Products shall be applied to a glass slide when appropriate. Products requiring a reactive substrate shall be applied to the appropriate alternate substrate. Coating products shall be applied using application conditions as specified by the manufacturer in the product use instructions, e. g., the highest recommended percentage of thinner, the shortest curing period between coats or layers, the maximum recommended film thickness per coat, and the shortest final curing period prior to immersion. For exothermic coatings with a maximum field use thickness in excess of 120 mil (3.0 mm), an additional evaluation at the manufacturer’s minimum recommended field use thickness shall be conducted. The maximum dry film thickness per coat attested to by the testing laboratory shall be based on the average per coat dry film thickness evaluated.
NOTE – The practical application of coatings may result in spots of coating thicknesses in excess of the maximum dry film thickness per coat attested to by the testing laboratory. Acceptable variations from the maximum dry film thicknesses can occur. The average of spot measurements on each 10 m2 (100 ft2) area shall not exceed the specified maximum thickness and no single spot measurement shall be more than 120% of it. Spot measurements are defined as the average of at least three gauge readings within a 1.5 in (4 cm) diameter circle.

Multiple layer paint and coating systems, which require the application of distinct coating product formulations in sequence, shall be applied in a stepped manner so as to expose all layers. Multiple coats of the same product (of the same color) applied in sequence shall not constitute multiple layers and shall not be applied in a stepped manner. Multiple coats of the same product (of different colors) applied in sequence shall not constitute multiple layers and shall not be applied in a stepped manner, unless deemed necessary by the testing laboratory to address potential health effects concerns from the differences in color formulations. Stepped coating systems shall be applied per the dimensions in table 5.1.
NOTE – It is recognized that a coating system may be applied using a combination of factory and field application techniques. This is considered acceptable as long as the coating system is tested to the manufacturer’s recommended application conditions, as specified in 5.5.2.2 and 5.5.2.3.

5.5.2.4 Products requiring cement mortar cubes Test sample mortar cubes shall be prepared in accordance to the applicable sections of ASTM C 109. Mix water shall meet reagent water requirements (see annex B, section B.9.2.1). Sand shall be washed in accordance with the procedures in ASTM C 778. Mixing tools and other items coming into contact with the mortar shall be washed with soap and water, rinsed with tap water, rinsed with reagent water, and rinsed with isopropyl alcohol. The mortar shall be placed in polyethylene or polypropylene lined molds; no form release agents shall be used. Specimens shall be removed from the molds after 24 h and placed in glass or polyethylene beakers and covered with an inverted watch glass supported on glass Rebel hooks (or other devices to prevent air seal of the vessel) and placed for 28 d ± 12 h, or fewer as specified by the manufacturer, in a moist cabinet meeting the requirements of ASTM C 511. The specimens shall be removed from the moist cabinet and air dried at 23 ± 2 °C (73 ± 4 °F) and 50 ± 2% relative humidity for 7 d. 5.5.2.4.1 Portland and hydraulic cements

Test cubes for Portland and blended hydraulic cements shall be prepared in accordance with 5.5.2.4. 5.5.2.4.2 Admixtures

Admixtures shall be added to the cement-mortar or concrete mixture using the manufacturer’s highest recommended admixture dosage. The test samples shall be prepared as described in 5.5.2.4. 5.5.2.4.3 Sealers

These products shall be applied per the manufacturer’s recommendations to the test cubes prepared in accordance with 5.5.2.4. The coated cubes shall be allowed to cure for the manufacturer’s recommended time period.

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5.5.2.4.4

Form and mold release agents

These products shall be applied per manufacturer specifications to the mold used during the preparation of the test cubes (see 5.5.2.4). 5.5.2.5 Concrete water storage tanks Concrete test cylinders (4" x 8") shall be prepared according to ASTM C 31 or ASTM C 192, and moist cured in an ASTM C 511 cabinet for a minimum of 3 d. Cylinder molds shall be manufactured of virgin materials free of detectable concentrations of any interfering contaminants. 5.5.3 Exposure water

Exposure water selection shall be determined by the analytes of interest identified on the analytical summary (see 5.5.1). Exposure water(s) shall be selected in accordance with annex B, section B.2.5. 5.5.4 Conditioning

Test samples shall be conditioned immediately after curing. This conditioning procedure simulates the disinfection of water storage tanks prior to placing into service. The method, described below, is based on Method 2 of AWWA C652-92. 1) prepare 200 mg/L available chlorine solution using sodium hypochlorite (NaOCl – reagent grade or equivalent); 2) using a spray bottle, spray the previously rinsed test samples, wetting all surfaces to be exposed; 3) let the test samples stand for at least 30 min; and 4) place the test samples in racks, rinse with cold tap water, and rinse with reagent water that meets the requirements of annex B, section B.9.2.1. 5.5.5 Exposure protocols

For all test samples, exposure shall commence immediately after the conditioning step. If immediate exposure is not possible, the test samples shall be dried in a laminar flow hood and exposed within 4 h. Successful evaluation at an elevated exposure temperature shall preclude testing at a lower exposure temperature. A separate sample shall be exposed for each type of exposure water selected in 5.5.3. The exact surface-area-to-volume ratio achieved during the exposure shall be recorded. 5.5.5.1 Cold application Cold application product samples, as designated by the manufacturer, shall be placed in an exposure vessel and completely covered with exposure water of the applicable pH (see annex B, section B.2.5). The exposure vessel shall be placed in a 23 ± 2 °C (73 ± 4 °F) environment for the duration of the exposure period. 5.5.5.2 Domestic hot application Products that are intended for domestic hot applications as designated by the manufacturer (e. g., for use in single-family dwellings) shall be placed in an exposure vessel and completely covered with exposure water of the applicable pH (see annex B, section B.2.5). The exposure vessel shall be placed in a 60 ± 2 °C (140 ± 4 °F) environment for the duration of the exposure period.

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5.5.5.3 Commercial hot application Products that are intended for commercial hot applications, as designated by the manufacturer (e. g., for use in multiple-family dwellings, restaurants, or hospitals), shall be placed in an exposure vessel and completely covered with exposure water of the applicable pH (see 5.5.3). The exposure vessel shall be placed in an 82 ± 2 °C (180 ± 4 °F) environment for the duration of the exposure period. 5.5.5.4 Single time point exposure protocol When normalized contaminant concentrations from the product are expected to be less than their acceptable concentrations (see annex A) when tested at a single time point (e. g., flexible membrane liners), the product shall be exposed according to the protocol in table 5.2. Extraction water samples shall be collected at the conclusion of the final exposure period. 5.5.5.5 Multiple time point exposure protocol When the normalized concentration of a contaminant exceeds, or is expected to exceed, its acceptable concentration (see annex A) when evaluated at a single time point (see 5.5.5.4), determination of the contaminant leaching rate as a function of time shall be considered. The relationship between contaminant concentration(s) and time shall be determined and plotted using a minimum of five data points. Table 5.3 summarizes the multiple time point exposure sequence. For contaminants of interest that do not require overtime testing, extraction water shall be collected after the third exposure period (elapsed time 5 d). 5.5.6 Collection and preservation of extraction water

Immediately after the exposure period, the extraction water shall be poured into previously prepared sample containers for storage as detailed in annex B, section B.6, until analysis. Extraction water for solvent analysis shall be collected in a sample bottle containing sodium thiosulfate in a quantity sufficient to neutralize any residual chlorine, if applicable. 5.6 Analysis of extraction water Extraction waters shall be analyzed with the methods listed in annex B, section B.8. 5.7 Normalization 5.7.1 Normalization for tanks/storage vessels

5.7.1.1 The following equation shall be used to calculate the normalized concentration of each contaminant for tanks or other storage vessels: normalized contaminant = concentration where: SAF/VF = Surface area to volume ratio for the specified tank capacity, as defined in table 5.4 SAL = Surface area exposed in the laboratory VL = Volume of extraction water used in the laboratory laboratory contaminant concentration x SAF VF x 24 h VL x SAL hours of exposure

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When the length of the exposure being normalized is other than 24 h in length, the normalized value shall be adjusted to reflect a 24-h exposure. Products used as barriers for tanks or storage vessels shall use the surface-area-to-volume ratios shown in table 5.4. Surface-area-to-volume ratios for products used as barriers in tanks or storage vessels with a capacity other than those shown in table 5.4 shall be determined on a case-by-case basis, as described in 5.7.1.2. 5.7.1.2 Calculation of the surface-area-to-volume ratio for tanks or storage vessels The following assumptions shall be used in determining the surface-area-to-volume ratio for each nominal tank capacity: – – – – the tank has a smooth interior surface; the tank is cylindrical in shape; the tank is installed in a vertical position; and the roof (ceiling) of the tank is in contact with drinking water.

The following equation shall be used to calculate the surface-area-to-volume ratio for tanks or storage vessels of capacities that do not appear in table 5.4: surface area to volume ratio (in2/L) = 119.5 x where: X = the length/diameter ratio of the tank or storage vessel Y = the volume (in gallons) of the tank or storage vessel 5.7.2 Normalization for all other end uses (0.1702 x Y/X)0.66 x (X + 1/2) Y

For barrier materials that have end uses other than in tanks or storage vessels, normalization shall be performed using the following equation, or to the normalization requirements of the section of this Standard which addresses the specific end use of the barrier material. NF N1 N2 where: SAF = surface area exposed in the field; SAL = surface area exposed in the laboratory; VL = volume of extraction water used in the laboratory; VF(static) = volume of water to which the product is exposed under static conditions; and VF(flowing) = volume of water to which the product is exposed under flowing conditions during a period of time equivalent to the laboratory test. = = = N1 x N2 SAF SAL VF(static) VF(flowing) x VL VF(static)

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When the length of the exposure being normalized is other than 24 h in length, the normalized value shall be adjusted to reflect a 24-h exposure (e. g., multiply the normalized value by 24/72 when a 3-d exposure was used). 5.7.3 Over time exposure calculations

Laboratory values from each time point for which extractant water was collected (a minimum of five data points is required) shall be normalized as indicated in 5.7.1 or 5.7.2, depending on product end use. A decay curve of these normalized contaminant concentrations in relation to elapsed exposure time shall be plotted. A contaminant concentration at Day 90 of exposure shall be extrapolated from this data.
NOTE – Day 1 is defined as the time point at which extractant water for all contaminants is collected for analysis (5 d of elapsed time). Day 90 is defined as 90 d after this time point (95 d of elapsed time).

5.8 Evaluation of contaminant concentrations 5.8.1 Contaminants measured at a single time point

Normalized contaminant concentrations shall be no greater than their respective SPACs determined in accordance with annex A. 5.8.2 Contaminants measured over time

Normalized Day 1 contaminant concentrations shall not exceed the short-term exposure level (STEL) as defined in annex A, section A.5. Extrapolated Day 90 contaminant concentrations shall not exceed their respective SPACs determined in accordance with annex A.

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? 2007 NSF Table 5.1 – Paint and coating system sample preparation Number of layers in system one layer two layer top layer primer layer three layer intermediate layer top layer primer layer first intermediate layer four layer second intermediate layer top layer
NOTE – A layer is one or more coats of the same coating material.

NSF/ANSI 61 – 2007

Layer ― primer layer

Panel surface area exposed for each layer entire panel 1/3 2/3 1/6 1/3 1/2 1/12 1/6 1/4 1/2

Table 5.2 – Single time point exposure sequence Length of exposure 24 ± 1 h 24 ± 1 h 48 ± 4 h 24 ± 1 h Elapsed time 1d 2d 4d 5d Sample collection discard extractant water and refill discard extractant water and refill discard extractant water and refill extractant water collected for analysis at conclusion of exposure period

NOTE – Sample exposures are sequential: decant and discard extraction water, refill container, and continue exposure.

Table 5.3 – Multiple time point exposure sequence Length of exposure 24 ± 1 h 24 ± 1 h 48 ± 4 h 24 ± 1 h 6±1d 24 ± 1 h 6±1d 24 ± 1 h 6±1d 24 ± 1 h 6±1d 24 ± 1 h Elapsed time 1d 2d 4d 5d 11 d 12 d 18 d 19 d 25 d 26 d 32 d 33 d Sample collection extractant water collected for analysis extractant water collected for analysis discard extractant water and refill extractant water collected for analysis discard extractant water and refill extractant water collected for analysis discard extractant water and refill extractant water collected for analysis discard extractant water and refill extractant water collected for analysis discard extractant water and refill extractant water collected for analysis

NOTE – Sample exposures are sequential: decant required volume for analysis when indicated, discard any remaining extraction water, refill container, and continue exposure.

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NSF/ANSI 61 – 2007 Table 5.4 – Surface-area-to-volume ratios for tanks or storage vessels

Nominal capacity (gal) 5 10 25 50 75 100 200 300 400 500 600 700 800 900 1,000 1,500 2,000 3,000 4,000 5,000 6,000 7,000 8,000 9,000 10,000 20,000 30,000 40,000 50,000 60,000 70,000 80,000 90,000 100,000 200,000 250,000 500,000 750,000 1,000,000 1,500,000 2,000,000 5,000,000 7,500,000 10,000,000
1

Surface area (ft2)1 5.3 8.4 15.5 22.0 28.9 35.0 55.1 71.3 85.8 99.0 110 121 132 141 150 196 238 312 378 438 495 548 600 648 696 1,104 1,447 1,753 2,034 2,297 2,545 2,782 3,010 3,228 5,125 5,946 9,439 12,370 14,980 19,630 23,780 43,810 57,400 69,530

Length/diameter ratio 5.0 5.0 5.0 3.0 3.0 3.0 2.9 2.7 2.6 2.5 2.3 2.2 2.1 1.9 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8

Surface-area-to-volume ratio (in2/1 L) 40.4 32.0 23.6 16.8 14.6 13.3 10.5 9.0 8.2 7.5 7.0 6.6 6.3 5.9 5.7 5.0 4.5 4.0 3.6 3.3 3.1 3.0 2.9 2.7 2.6 2.1 1.8 1.7 1.6 1.5 1.4 1.32 1.27 1.23 0.97 0.90 0.72 0.63 0.57 0.50 0.45 0.33 0.29 0.26

Surface area calculations include the sides, floor, and roof (ceiling) of a tank.

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6 Joining and sealing materials
6.1 Coverage This section covers materials that join or seal pipes and related products (e. g., tanks); protective (barrier) materials; and mechanical devices that contact drinking water. 6.2 Definitions 6.2.1 flux: A formulation intended to remove traces of surface oxides, to promote wetting, and to protect surfaces to be soldered or brazed from oxidation during heating. 6.2.2 6.2.3 gaskets and sealing materials: Materials used to fill a hole or joint to prevent leakage. joining materials: Materials that form a bond when used to put parts together.

6.2.4 lubricant: A substance interposed between two surfaces for the purpose of reducing the friction or wear between them. 6.3 Material and extraction testing requirements Samples for testing shall be prepared as specified by the manufacturer's written instructions, and exposed as outlined in annex B. Any contaminants extracted shall have normalized concentrations no greater than the limits specified in annex A. 6.4 Items of special significance The manufacturer shall supply written information relative to the product's intended end uses and applications.

7 Process media
7.1 Scope The requirements in this section apply to process media products intended for the reduction of dissolved or suspended materials present in drinking water. The products that are covered include, but are not limited to, process media used in the following processes: ion exchange, adsorption, oxidation, aeration, and filtration. 7.2 Definitions 7.2.1 adsorption: The retention of a gas, liquid, solid, or dissolved material onto the surface of a solid.

7.2.2 adsorption media: A process media material upon which a gas, liquid, solid, or dissolved material will be retained. 7.2.3 aeration: The process of bringing water into contact with air in order to expedite the transfer of gas between the two phases. 7.2.4 aeration packing media: Media used in aerators to increase the surface area of the liquid being processed, resulting in increased liquid-to-air contact and improved gas transfer. 7.2.5 filtration: The process of passing a dilute liquid suspension through filter media to reduce the concentration of suspended or colloidal matter.

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7.2.6

filtration media: Process media through which a liquid is passed for the purpose of filtration.

7.2.7 ion exchange: A chemical process in which ions are reversibly interchanged between a liquid and a solid. 7.2.8 ion exchange resins: Process media consisting of insoluble polymers having functional groups capable of exchanging ions. 7.2.9 low-density process media: Process media such as diatomaceous earth, perlite, or other media, which have a bulk density of less than 500 g/L and are used for filtration purposes. 7.2.10 oxidative media: Process media that chemically facilitate oxidation on the media surface and thereby enhance removal of ions from water. 7.2.11 process media: Water insoluble material used to reduce the concentration of dissolved or suspended substances in water through such operations as ion exchange, aeration, adsorption, oxidation, and filtration. 7.2.12 reductive media: Process media that chemically facilitate reduction on the media surface and thereby enhance removal of ions from water. 7.3 General requirements 7.3.1 Manufacturer use instructions

All process media products shall be accompanied by detailed manufacturer use instructions that shall also appear on the product packaging or other technical literature. For process media products that are dosed (e. g., powdered activated carbon), use instructions shall include the maximum dose at which the product can be acceptably used (as determined by evaluation to the requirements of this section). 7.3.2 Product labeling

Process media product containers shall facilitate traceability to the production location and shall, at a minimum, contain the following information: – – – – – – – 7.3.3 manufacturer's name and address; production location identifier; product identification (product type and, when applicable, trade name); net weight; when applicable, mesh or sieve size; lot number; and when appropriate, special handling, storage, and use instructions.

Product line evaluation

When a line of products is manufactured to the same material formulation and contains identical ingredients, product evaluation shall be preferentially conducted on the product form that has the highest surface-area-to-volume ratio (smallest particle size). Products of a lower surface-area-to-volume ratio (larger particle size) shall be considered to have met the requirements of this section when a higher surface-area-to-volume ratio product, belonging to the same line of products and having an identical use, has been demonstrated to meet the requirements of this section.

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A representative sample of the media shall be reduced to three test samples, each of a sufficient quantity for the extraction procedures described in 7.5. The three test samples shall be placed and stored in airtight, moisture-proof, sealed glass containers. If a glass container is inappropriate, containers made from some other inert material recommended by the manufacturer shall be used. Each container shall be clearly labeled with product name, type of sample, manufacturer name, sampling data, production location, lot number, and the name of the individual who collected the sample. One sample shall be used for exposure and analysis; the remaining two samples shall be retained for re-evaluation purposes. 7.5 Extraction procedures 7.5.1 Analytical summary

An analytical summary shall be prepared for each product. The analytical summary shall consist of the formulation-dependent analytes identified in accordance with 3.3 and the applicable product-specific minimum test batteries listed in table 7.1. 7.5.2 Wetting

Process media that receive conditioning shall be immersed completely (wetted) in tap water prior to conditioning and exposure. The weight of the sample to be wetted shall be at least equal to the amount of media required to perform the exposure at the specified weight-to-volume ratio (see 7.5.5 and table 7.2). For example, with a media for which 2 L (0.53 gal) of extractant water is required to perform the selected analyses, if the media is exposed at 25 g/L, a minimum of 50 g of media is wetted. For low-density process media, 0.5 L (0.13 gal) of the process media shall be wetted; the weight of this volume of media shall be measured and recorded prior to wetting. After the specified wetting period, the sample shall be completely drained and the water discarded. 7.5.2.1 Granular activated carbon Granular activated carbon (GAC) test samples shall be wetted for 16 ± 1 h. 7.5.2.2 Other process media products All other process media that receive conditioning shall be wetted for 60 ± 10 min. 7.5.3 Conditioning (backwashing)

7.5.3.1 Filtration and adsorption media Wetted filtration or adsorption media (excluding diatomaceous earth, perlite, and powdered activated carbon (PAC) products, and other media of < 0.25 mm diameter) shall be placed in a conditioning chamber (a glass column with a minimum inner diameter of 2 in). The amount of media conditioned shall be sufficient to meet or exceed its specific weight-per-volume ratio (see table 7.2) and to generate sufficient exposure water to complete the selected analyses. Tap water shall be directed slowly upward through the conditioning system until the entire amount of media is flooded. The media shall then be backwashed at a flow rate that fluidizes the media or attains sufficient transport velocities to remove extraneous particulate matter; the maximum wetted media expansion rates for various process media products are indicated in table 7.3. Filtration and adsorption media shall be subjected to the prescribed backwash for 30 ± 2 min.

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Diatomaceous earth, perlite, PAC, and all other process media with functions other than filtration or adsorption shall not be conditioned unless the manufacturer’s use instructions stipulate a specific conditioning protocol. 7.5.3.3 Special post-conditioning procedures for sand and anthracite products Upon completion of the backwash, 1% to 1.5% of the sand or anthracite column (by height) shall be scraped away and discarded. 7.5.4 Exposure water

All exposure water that is being used to determine compliance to this Standard shall be prepared fresh daily and stored in a closed container. 7.5.4.1 Adsorption media Adsorption media shall be exposed in a pH 5 sodium dihydrogen phosphate buffer, prepared by mixing 0.1 M NaH2PO4, 0.04 M MgCl2, and reagent water that meets the requirements of annex B, section B.9.2.1, at a ratio of 1:1:18, respectively. 7.5.4.2 All other process media All other process media shall be exposed in reagent water that meets the requirements of annex B, section B 9.2.1. 7.5.5 Exposure protocols

Table 7.2 contains the weight-per-volume ratios for exposure of process media. 7.5.5.1 Adsorption media 7.5.5.1.1 Media of < 0.25 mm in diameter

Immediately after completion of wetting, the media sample shall be exposed in an appropriately sized vessel. The amount of media exposed per volume of exposure water (see 7.5.4.1) shall be sufficient to meet or exceed its specific weight-per-volume ratio according to table 7.2, and to generate sufficient exposure water to complete the selected analyses. The vessel shall be covered and placed on a magnetic stirrer for 60 ± 5 min. Immediately after the exposure period, the liquid portion of the exposure shall be passed through a Whatman13 #41 filter and a 0.45 μ filter, and the resulting filtrate shall be collected. The solid portion of the exposed sample remaining on the filter shall be dried and weighed, and used to calculate the evaluation dose. 7.5.5.1.2 Media of ≥ 0.25 mm in diameter

Immediately after completion of conditioning, the media sample shall be exposed in an appropriately sized vessel. The amount of media exposed per volume of exposure water (see 7.5.4.1) shall be sufficient to meet or exceed its specific weight-per-volume ratio in table 7.2 and to generate sufficient exposure water to complete the selected analyses. The contents of the vessel shall be mixed to ensure that the entire sample is in contact with the exposure water. The vessel shall be sealed with polytetrafluoroethylene (PTFE), and the sample shall be exposed according to the schedule outlined in table 7.4. The weight-to-volume ratio shall be recorded at the time of exposure and shall represent the evaluation dose.
13

Whatman PLC, 27 Great West Road, Brentford, Middlesex TW8 9BW, UK

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7.5.5.2 Filtration media, ion exchange resins, synthetic media, and all other process media Immediately after completion of wetting, or conditioning if applicable, the media sample shall be exposed in an appropriately sized vessel. The amount of media exposed per volume of exposure water (see 7.5.4.2) shall be sufficient to meet or exceed its specific weight-per-volume ratio in table 7.2 and to generate sufficient exposure water to complete the selected analyses. The contents of the vessel shall be mixed to ensure that the entire sample is in contact with the exposure water. The vessel shall be sealed with PTFE, and the sample shall be exposed according to the schedule outlined in table 7.4. The weightto-volume ratio shall be recorded at the time of exposure and shall represent the evaluation dose. 7.5.5.3 Aeration packing media Aeration packing media shall be exposed in appropriately sized vessels at a surface-area-to-volume ratio greater than or equal to its manufacturer’s recommended field surface-area-to-volume ratio and in a volume of exposure water sufficient to complete the selected analyses. The vessel shall be sealed with PTFE, and the sample shall be exposed according to the schedule outlined in table 7.4.
NOTE – The volume of extraction water can be proportionately increased if an additional amount of media was prepared in order to complete the selected analyses.

7.5.6

Collection and preservation of extraction water

Immediately after exposure, extraction waters shall be poured into previously prepared sample containers for storage until analysis, as specified in annex B, section B.6. 7.6 Analysis Extraction waters shall be analyzed with the methods listed in annex B, section B.7. 7.7 Normalization The concentration of analytes present in the extraction water shall be multiplied by calculated normalization factors to account for differences between the actual laboratory evaluation ratio and the weight-per-volume ratio in table 7.2. 7.7.1 Process media except for activated carbon media and aeration packing media

The concentration reported by the laboratory shall be normalized with the following equation (Equation 1): normalized laboratory weight per volume ration (mg/L) contaminant = contaminant x laboratory evaluation ratio (mg/L) concentration concentration This equation shall be used to normalize filtration media, ion exchange resins, synthetic media, and other media to the weight-per-volume ratios listed in table 7.2. 7.7.2 Activated carbon media

The concentration reported by the laboratory shall be normalized with the following equation (Equation 2): normalized laboratory 250 mg/L contaminant = contaminant x laboratory evaluation ratio (mg/L) concentration concentration

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Equation 2 shall be used to normalize activated carbon media (granular or powdered) to a weight-pervolume ratio of 250 mg/L. 7.7.3 Filter precoat media (e. g., perlite, diatomaceous earth)

The concentration reported by the laboratory shall be normalized with the following equation (Equation 3): normalized laboratory manufacturer’s use concentration (mg/L) contaminant = contaminant x laboratory evaluation ratio (mg/L) concentration concentration Equation 3 shall be used to normalize dosed media (except PAC) to the manufacturer’s recommended maximum use concentration. 7.7.4 Aeration packing media

The concentration reported by the laboratory shall be normalized with the following equation (Equation 4): normalized laboratory SAF VF x contaminant = contaminant x VF(flowing) SAL concentration concentration where: SAL = surface area attained during laboratory exposures; VL = volume of exposure water used during laboratory exposures; SAF = surface area of the product under field conditions; and VF(flowing) = minimum volume of water to which the product is exposed in the field under flowing conditions during a period of time equivalent to the laboratory evaluation.
NOTE – When manufacturer use instructions indicate that the aeration product can be subjected to static conditions in the field, normalized concentrations shall be modified to reflect the static condition. For the static condition, the VF(flowing) parameter shall be substituted with VF(static), which is equal to the volume of water contacting the media under static conditions in the field.

7.8 Evaluation of contaminant concentrations 7.8.1 For process media, normalized contaminant concentrations shall be no greater than their respective SPACs, determined in accordance with annex A. 7.8.2 For aeration packing media that require evaluation to the static condition, the normalized static contaminant concentrations shall be no greater than their respective MCLs or TACs determined in accordance with annex A.

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Table 7.1 – Product-specific minimum test batteries for process media products Product activated alumina aluminum silicates (e. g., zeolites) anthracite diatomaceous earth media garnet granular activated carbon (GAC) gravel ilmenite ion exchange resins oxidative media (e. g., manganese green sand) perlite powdered activated carbon (PAC) sand synthetic media
1

Primary use adsorption filtration filtration filtration filtration adsorption filtration filtration ion exchange oxidation filtration adsorption filtration aeration, filtration

Analytes metals1, nickel, and aluminum metals1, GC/MS (base neutral and radionuclides metals1, GC/MS (base neutral and radionuclides metals1 and radionuclides metals1, GC/MS (base neutral and radionuclides metals1, GC/MS (base neutral and radionuclides metals1, GC/MS (base neutral and radionuclides metals1, GC/MS (base neutral and radionuclides residual monomer, other dependent metals1, GC/MS (base neutral and radionuclides metals1, GC/MS (base neutral and radionuclides metals1, GC/MS (base neutral and radionuclides metals1, GC/MS (base neutral and radionuclides formulation dependent

acid scans), acid scans),

acid scans), acid scans), acid scans), acid scans), formulation acid scans), acid scans), acid scans), acid scans),

Metals = antimony, arsenic, barium, beryllium, cadmium, chromium, copper, lead, mercury, selenium, thallium

Table 7.2 – Process media exposure weight-per-volume ratios Media type adsorption media: activated alumina GAC and PAC anthracite and gravel2: ≤ 3/8" diameter particles > 3/8" diameter particles filter precoat media (e. g, perlite, diatomaceous earth) filtration media other than anthracite or gravel ion exchange resins synthetic media
1 2

Weight-per-volume1 625 ± 25 g/L 25 ± 5 g/L 625 ± 25 g/L 1250 ± 25 g/L 10 times the manufacturer’s recommended use concentration 625 ± 25 g/L 625 ± 25 g/L 625 ± 25 g/L

Weight-per-volume of the product on an “as shipped” basis.

For the size range specified, not more than 8% by weight shall be either finer than or coarser than the designated size limit (AWWA B100-96).

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Table 7.3 – Maximum conditioning expansion rates for filtration and adsorption media Media type activated alumina aluminum silicates (zeolites) anthracite garnet granular activated carbon gravel ilmenite manganese greensand sands Maximum laboratory expansion rate of wetted media (by height) (%) 25 ± 5% 25 ± 5% 25 ± 5% 30 ± 5% 30 ± 5% 10 ± 5% 30 ± 5% 30 ± 5% 20 ± 5%

Table 7.4 – Exposure schedule for process media of ≥ 0.25 mm in diameter Time 60 ± 5 min 60 ± 5 min 60 ± 5 min Temperature 23 ± 1 °C (73 ± 2 °F) 23 ± 1 °C (73 ± 2 °F) 23 ± 1 °C (73 ± 2 °F) Comment Exposure water is drained/decanted and discarded; the exposure vessel is refilled and exposure is continued. Exposure water is drained/decanted and discarded; the exposure vessel is refilled and exposure is continued. Exposure water is collected and filtered for analyses.

8 Mechanical devices
8.1 Coverage This section covers devices, components, and materials used therein, that are used in treatment/ transmission/distribution systems and are in contact with drinking water intended for human ingestion, drinking water treatment chemicals, or both. Examples are listed in table 8.1. Residential point-of-use and point-of-entry drinking water treatment devices and fire hydrants are not covered by the requirements in this section. 8.2 Definitions 8.2.1 cold water application: A product application that is intended to result in continuous exposure to water of ambient temperature. Products are tested for an end-use temperature of 23 ± 2 °C (73 ± 4 °F). 8.2.2 commercial hot water application: A product application that is intended to result in continuous or intermittent exposure to water that has been raised from ambient temperature. Intermittent exposure is defined as any hot water contact that is not continuous. Products are tested for an end-use temperature of 82 ± 2 °C (180 ± 3 °F). 8.2.3 domestic hot water application: A product application that is intended to result in continuous or intermittent exposure to water that has been raised from ambient temperature. Intermittent exposure is defined as any hot water contact that is not continuous. Products are tested for an end-use temperature of 60 ± 2 °C (140 ± 3 °F). 8.2.4 in-line device: A device (used to measure or control the flow of water) installed on a service line or building distribution system downstream of the water main and upstream of endpoint devices. 8.2.5 building distribution system: A continuous system of piping and related fittings, beginning at the tap on the main, that is intended to convey potable water to points of usage.

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8.3 Device, component, or material requirements 8.3.1 General

Devices, components, or materials shall be considered to have met the requirements of this section if at least one of the following conditions is met: – the devices, components, or materials covered under this section are tested and evaluated according to the procedures specified in annex B, sections B.4 and B.8; or – the devices, components, or materials meet the requirements of 8.3.2.

When all components or materials, or both, of a device meet the requirements of this section, the device shall also meet the requirements of this section. When all materials of a component meet the requirements of this section, the component shall also meet the requirements of this section. 8.3.2 Evaluation of devices, components, or materials tested to other sections of this Standard

Devices, components, or materials that have been tested to other sections of the Standard shall meet the following criteria: – – they shall be made of the same alloy(s), composition(s), or formula(s); they shall have undergone analogous manufacturing processes;

– they shall have been tested at a temperature that meets or exceeds the required exposure temperature in annex B, section B.4; – they shall have been conditioned for a period of time not more than 14 d, and exposed for a period of time not less than 12 h for in-line devices or 24 h for other mechanical devices; and – the concentration(s) of the extracted contaminant(s) shall be normalized to the requirements of annex B, section B.8. 8.3.3 Metallic contaminants

When a device or component is qualified through the separate testing of two or more components, the normalized concentrations for each specific metallic contaminant from individual components shall be summed. The total of the normalized metallic contaminant concentrations shall meet the requirements of annex B, section B.8. 8.4 In-line devices, components, and materials Samples for the testing of in-line devices, components, and materials (see 8.1) shall be selected according to the requirements of annex B, sections B.2.3 and B.4.1. Extraction waters shall be selected according to annex B, section B.2.5. In-line product samples shall be conditioned as indicated in annex B, section B.4.3. After conditioning, the samples shall be exposed as indicated in annex B, section B.4.4.1 and table B8. Normalization shall be as specified in annex B, sections B.8.3 and B.8.4, as applicable. 8.5 Chemical feeders and generators Samples for the testing of chemical feeders and generators shall be selected according to the requirements of annex B, sections B.2.3 and B.4.1. Chemical feeder and generator samples shall be conditioned as indicated in annex B, section B.4.3. After conditioning, the samples shall be exposed as indicated in annex B, section B.4.4.2. Normalization shall be as specified in annex B, section B.8.5.

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8.6 Other mechanical devices, components, and materials Samples for the testing of all other mechanical devices, components, and materials shall be selected according to the requirements of annex B, sections B.2.3 and B.4.1. Extraction waters shall be selected according to annex B, section B.2.5. Other mechanical product samples shall be conditioned as indicated in annex B, section B.4.3. After conditioning, the samples shall be exposed as indicated in annex B, section B.4.4.3 and table B9. Normalization shall be as specified in annex B, sections B.8.3, B.8.4, and B.8.6, as applicable. Table 8.1 – Examples of mechanical devices This table is a generic listing of the types of devices covered in this section of the Standard. This table is not intended to be a complete list of all types of mechanical devices. Inclusion of a product does not indicate either a use endorsement of the product or an automatic acceptance under the provisions of this Standard. chemical feeders – dry feeders (e. g., pellet droppers) pressure gas injection systems pumps vacuum injection systems disinfection/generators – – – – chlorine dioxide hypochlorite ozone ultraviolet valves and related fittings (transmission/distribution system) treatment devices used in water treatment facilities (excludes residential point-of-use and point-of-entry devices) – – – – – – – – – – – – – – – – aeration technologies clarifiers electrodialysis technologies microfiltration technologies mixers reverse osmosis technologies screens strainers ultrafiltration technologies meter stops pressure regulators pressure tanks service saddles strainers valves and fittings water meters switches and sensors (e. g., water level, pressure, temperature, pH)

electrical wire (e. g., submersible well pump wire) pumps in-line devices – building distribution system – backflow preventers – building valves – check valves – compression fittings – corporation stops – curb stops – expansion tanks – meter couplings in-line devices specifically excluded – boiler feed valves – drilling and tapping machines – temperature and pressure relief valves – valves with hose thread outlets – water meter test benches

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9 Mechanical plumbing devices
9.1 Coverage This section covers mechanical plumbing devices, components, and materials that are typically installed within the last liter of the distribution system (endpoint devices) and are intended to dispense water for human ingestion. In-line devices are excluded from this section. Point-of-use and point-of-entry water treatment devices are excluded. 9.1.1 Endpoint devices specifically included in the coverage of this section are: – single-handle and two-handle lavatory faucets (e. g., centersets, widespread, mini-spread, and basin cocks), except as exempted in 9.1.2; – two-hole and single-hole bar faucets;

– single-handle and two-handle kitchen faucets (e. g., top mounts, concealed fittings, and wall mounts) with or without a side spray component; – – – – – – hot and cold water dispensers; drinking fountains, drinking fountain bubblers, and water coolers; glass fillers; residential refrigerator ice makers; supply stops and endpoint control valves; and commercial kitchen devices (see 9.2.3), limited to the following: – – – pot and kettle fillers (see 9.2.7); devices with extended standpipes or risers (see 9.2.5); and pre-rinse assemblies that include an auxiliary spout or other outlet.
NOTE 1 – Only the commercial kitchen devices listed above shall be evaluated using the 18.9 L (5 gal) normalization. NOTE 2 – The base device to which the pre-rinse component is added shall be considered a commercial kitchen device only if it meets the definition of either a pot and kettle filler (see 9.2.7) or a device with extended standpipes or risers (see 9.2.5).

9.1.2

Endpoint devices specifically exempted from the coverage of this section are: – – – – bath and shower valves, shower heads of all types, and Roman tub valves; drains; backflow prevention devices; pre-rinse assemblies that do not include an auxiliary spout or other outlet; and

– endpoint devices that are not specifically intended to dispense water for human consumption, including utility, laundry, laboratory, bidet, and shampoo fittings; faucets with a hose thread spout

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end or with a quick disconnect end; faucets that are self-closing, metering, or electronically activated; and nonlavatory hand wash stations. 9.1.3 Endpoint devices that are exempted from the scope of this section shall be permitted to be evaluated at the option of the manufacturer. With the exception of exempted pre-rinse assemblies, all exempted devices shall be evaluated using the 1 L (0.26 gal) draw. Exempted pre-rinse assemblies shall be evaluated using the 18.9 L (5 gal) draw. 9.2 Definitions 9.2.1 cold mix volume adjustment factor (CMV): The cold water volume of a device divided by the total water volume of the device. 9.2.2 cold water volume: The volume of water contained within the portion of a device that is normally contacted by cold water (from inlet to outlet) when the device is connected to hot and cold water supplies under normal operating conditions. The volume excludes the volume of water contained within the portion of the device that is normally contacted only by hot water. 9.2.3 commercial kitchen device: An endpoint device whose sole application is the delivery of water for food preparation in commercial kitchens. 9.2.4 endpoint device: A single device typically installed within the last 1 L (0.26 gal) of the water distribution system of a building. 9.2.5 extended standpipe or riser device: An endpoint device that includes a vertical component having a minimum height of 41 cm (16 in) measured from the deck to the outlet of the endpoint device, and whose sole application is the delivery of water for food preparation in commercial kitchens. 9.2.6 in-line device: A device (used to measure or control the flow of water) installed on a service line or building distribution system downstream of the water main and upstream from endpoint devices. 9.2.7 pot and kettle filler: An endpoint device whose sole application is the delivery of water to fill pots and kettles in commercial kitchens. 9.2.8 pre-rinse assembly: An endpoint device with a hose and spray whose application is water delivery for the rinsing of tableware in commercial kitchens. 9.2.9 water distribution system (building): A continuous system of piping, devices, and related fittings, beginning after the water meter and water meter setting equipment, that is intended to convey potable water in a building to points of usage. 9.3 Device, component, or material requirements 9.3.1 General

Devices, components, or materials shall be considered to have met the requirements of this section if at least one of the following conditions is met: – The devices, components, or materials covered under this section are tested and evaluated according to procedures specified in annex B, sections B.5 and B.8; or – The devices, components, or materials meet the requirements of 9.3.2.

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When all components or materials, or both, of a device meet the requirements of this section, the device shall also meet the requirements of this section. When all materials of a component meet the requirements of this section, the component shall also meet the requirements of this section. 9.3.2 Evaluation of devices, components, or materials tested to other sections of this Standard

Devices, components, or materials that have been tested to other sections of this Standard shall: – – be made of the same alloy(s), composition(s), or formula(s); have undergone analogous manufacturing processes;

– have been tested at a temperature that meets or exceeds the required exposure temperature in annex B, section B.5; – have been conditioned for a period of time not more than 19 d and exposed for a period of time not less than 16 h; and – have the concentration(s) of the extracted contaminant(s) normalized to the requirements of annex B, section B.8. 9.3.3 Metallic contaminants

When a device or component is qualified through the separate testing of two or more components, the normalized concentrations for each specific metallic contaminant from individual components shall be summed. The total of the normalized metallic contaminant concentrations shall meet the requirements of 9.5. 9.4 Exposure and normalization Samples for testing shall be prepared and exposed, and the extractant water analyzed as required in annex B, section B.5. The number of samples tested shall be determined as outlined in annex B, section B.5. Exposure of endpoint samples, except for hot water dispenser samples, shall be performed at 23 ± 2 °C (73 ± 4 °F). For kitchen faucets with side spray components, the side spray component shall be prepared and exposed simultaneously with the remainder of the device. At the option of the manufacturer, a separate exposure may be performed for the side spray component. The concentration of extracted contaminants shall be normalized to end-use conditions according to the normalization procedure outlined in annex B, section B.8 for endpoint devices, components, and materials. All endpoint devices, components, and materials other than commercial kitchen devices shall be evaluated using the highest surface-area-to-volume product as the test sample, and shall be normalized using the 1 L (0.26 gal) first draw. Commercial kitchen devices shall be evaluated using the highest surface-area-to-volume product as the test sample, and shall be normalized using the 18.9 L (5 gal) first draw. 9.5 Evaluation of normalized contaminant concentrations 9.5.1 Evaluation of lead

For endpoint devices other than commercial kitchen devices, the lead test statistic Q shall not exceed 11 μg when normalized for the 1 L (0.26 gal) first draw sample. For commercial kitchen devices, the lead test statistic Q shall not exceed 11 μg when normalized for the 18.9 L (5 gal) first draw sample.

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NOTE – The limit of 11 μg for lead is based on a limit of 15 μg total lead, including lead contributed from the device interior as well as from sources other than the device, which is assumed to be 4 μg. For kitchen faucets that have been exposed simultaneously with the side spray component, the lead test statistic Q value for the entire assembly shall not exceed 11 μg. When the kitchen faucet and the side spray component have been exposed separately, the lead test statistic Q value for the faucet and side spray shall be added and shall not exceed 11 μg . 9.5.2 Evaluation of non-lead contaminants

For endpoint devices other than commercial kitchen devices, the normalized concentration of a nonlead contaminant shall not exceed its SPAC (calculated in accordance with annex A) when normalized for the 1 L (0.26 gal) first draw sample. For commercial kitchen devices, the normalized concentration of a nonlead contaminant shall not exceed its SPAC when normalized for the 18.9 L (5 gal) first draw sample. For kitchen faucets that have been exposed simultaneously with the side spray component, the normalized concentration of a non-lead metal contaminant for the entire assembly shall not exceed its SPAC. When the kitchen faucet and the side spray component have been exposed separately, the normalized concentration of a non-lead metal contaminant for the faucet and side spray shall be added and shall not exceed its SPAC.

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Annex A (normative) Toxicology review and evaluation procedures

A.1

General requirements

This annex defines the toxicological review and evaluation procedures for the evaluation of substances imparted to drinking water through contact with drinking water system components. It is intended to establish the human health risk, if any, of the substances imparted to drinking water under the anticipated use conditions of the product. Annex D (normative) and annex E (informative) of this Standard contain evaluation criteria that have been determined according to the requirements of this annex. The following general procedure shall be used to evaluate drinking water substances under this Standard: a) A determination shall be made as to whether a published (publicly available in printed or electronic format) and peer-reviewed quantitative risk assessment for the substance is available. b) When a quantitative risk assessment is available, the reviewer shall determine whether the assessment is currently used in the promulgation of a drinking water regulation or published health advisory for the substance (see the requirements of annex A, section A.3): – If the assessment is used in the promulgation of a drinking water regulation, the Single Product Allowable Concentration (SPAC) shall be derived from the regulatory value(s); or – If the assessment is not the basis of a drinking water regulation, the assessment and its corresponding reference dose shall be reviewed for their appropriateness in evaluating the human health risk of the drinking water substance.
NOTE – During the review of an assessment used in the promulgation of a drinking water regulation, it is recommended that the regulatory authority be contacted to verify that the assessment under consideration is current.

c) If a published and peer-reviewed quantitative risk assessment is not currently available for the substance, the Total Allowable Concentration (TAC) and SPAC shall be derived after review of the available toxicology data for the substance (see annex A, section A.4). – When the data requirements for qualitative risk assessment are satisfied (see annex A, section A.4.2 and table A1), a qualitative risk assessment shall be performed according to annex A, section A.7; or – When the data requirements for quantitative risk assessment are satisfied (see annex A, section A.4.3 and table A2), a quantitative risk assessment shall be performed according to annex A, section A.7. Figure A1, annex A, provides an overview of the toxicity data review requirements of this annex.

A.2

Definitions

A.2.1 benchmark dose: The lower 95% confidence limit on the dose that would be expected to produce a specified response in X% of a test population. This dose may be expressed as BMDX (adapted from Barnes et al., 1995).

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NOTE – For the purposes of this Standard, the benchmark dose shall be calculated at the 10% response level.

A.2.2 continuous data: A measurement of effect that is expressed on a continuous scale, e. g., body weight or serum enzyme levels (USEPA, 1995). A.2.3 critical effect: The first adverse effect, or its known precursor, that occurs as the dose rate increases (USEPA, 1994). A.2.4 ED10: Effective dose 10; a dose estimated to cause a 10% response in a test population (USEPA, 1996a). A.2.5 genetic toxicity: Direct interaction with DNA that has the potential to cause heritable changes to the cell. A.2.6 health hazards (types of) (USEPA, 1994 and 1999)

A.2.6.1 acute toxicity: Effects that occur immediately or develop rapidly after a single administration of a substance. Acute toxicity may also be referred to as immediate toxicity. A.2.6.2 allergic reaction: Adverse reaction to a chemical resulting from previous sensitization to that chemical or to a structurally similar one. A.2.6.3 chronic effect: An effect that occurs as a result of repeated or long-term (chronic) exposures. A.2.6.4 chronic exposure: Multiple exposures occurring over an extended period of time or a significant fraction of an animal’s or individual’s lifetime. A.2.6.5 chronic toxicity: The capability of a substance to cause adverse human health effects as a result of chronic exposure. A.2.6.6 irreversible toxicity: Toxic effects to a tissue that cannot be repaired. A.2.6.7 local toxicity: Effects that occur at the site of first contact between the biological system and the toxicant. A.2.6.8 reversible toxicity: Toxic effects that can be repaired, usually by a specific tissue’s ability to regenerate or mend itself after chemical exposure. A.2.6.9 systemic toxicity: Effects that are elicited after absorption and distribution of a toxicant from its entry point to its target tissue. A.2.7 LED10: Lowest effective dose 10; the lower 95% confidence limit on a dose estimated to cause a 10% response in a test population (USEPA, 1996a). A.2.8 lowest observed adverse effect level (LOAEL): The lowest exposure concentration at which statistically or biologically significant increases in frequency or severity of effects are observed between the exposed population and its appropriate control group (USEPA, 1994). A.2.9 margin of exposure (MOE): The LED10 or other point of departure, such as an NOAEL, divided by the environmental dose of interest (USEPA, 1996a). A.2.10 model: A mathematical function with parameters that can be adjusted so that the function closely describes a set of empirical data. A mathematical or mechanistic model is usually based on biological or physical mechanisms and has model parameters that have real-world interpretations. Statistical or

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empirical models are curve-fitted to data where the math function used is selected for its numerical properties and accuracy. Extrapolation from mechanistic models (e. g., pharmacokinetic equations) usually carries higher confidence than extrapolation using empirical models (e. g., logit) (USEPA, 1994). A.2.11 no observed adverse effect level (NOAEL): An exposure concentration at which no statistically or biologically significant increases in the frequency or severity of adverse effects are observed between an exposed population and its appropriate control. Some physiological effects may be produced at this concentration, but they are not considered toxicologically significant or adverse, nor are they considered precursors to adverse effects (USEPA, 1994). A.2.12 non-regulated substance: A substance for which a statutory concentration limit does not exist. A.2.13 peer review: A documented critical review of a scientific or technical work product conducted by qualified individuals or organizations who are independent of those who performed the work, but who are collectively equivalent or superior in technical expertise to those who performed the work. It includes an in-depth assessment of the assumptions, calculations, extrapolations, alternate interpretations, methodology, acceptance criteria, and conclusions pertaining to the work product and the documentation that supports the conclusions reached in the report. Peer review is intended to ensure that the work product is technically adequate, competently performed, and properly documented, and that it satisfies established requirements (USEPA, 1998). A.2.14 point of departure: A data point or an estimated point that can be considered to be in the range of observation. The standard point of departure is the LED10, which is the lower 95% confidence limit on a dose associated with 10% extra risk (adapted from Barnes et al., 1995). A.2.15 qualitative risk assessment: An estimation of the risk associated with exposure to a substance using a non-quantitative methodology. A.2.16 quantal data: A dichotomous measure of effect; each animal is scored “normal” or “affected,” and the measure of effect is the proportion of scored animals that are affected (USEPA, 1995). A.2.17 quantitative risk assessment: An estimation of the risk associated with exposure to a substance using a methodology that employs evaluation of dose response relationships. A.2.18 range of extrapolation: Doses that are outside the range of empirical observation in animal studies, human studies, or both (adapted from Barnes et al., 1995). A.2.19 range of observation: Doses that are within the range of empirical observation in animal studies, human studies, or both (adapted from Barnes et al., 1995). A.2.20 reference dose (RfD): An estimate (with uncertainty spanning approximately an order of magnitude) of a daily exposure to the human population (including sensitive subgroups) that is likely to be without an appreciable risk of deleterious effects during a lifetime (USEPA, 1994). A.2.21 regulated substance: A substance for which a quantitative human health risk assessment has been performed and utilized in promulgation of a statutory concentration limit for drinking water. A.2.22 toxicodynamics: Variations in the inherent sensitivity of a species or individual to chemicalinduced toxicity, resulting from differences in host factors that influence the toxic response of a target organ to a specified dose (TERA, 1996). A.2.23 toxicokinetics: Variations in absorption, distribution, metabolism, and excretion of a compound that account for differences in the amount of parent compound or active metabolite(s) available to a target organ (TERA, 1996).

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A.2.24 treatment technique: A technology or one or more procedures used to control the concentration of a substance in a drinking water supply when it is neither technically nor economically feasible to ascertain the concentration of the substance (U. S. Safe Drinking Water Act, 1996). A.2.25 weight of evidence: The extent to which the available biomedical data support the hypothesis that a substance causes cancer or other toxic effects in humans (adapted from USEPA, 1994).

A.3
A.3.1

Data requirements for published risk assessments
General requirements

Evaluation of all published risk assessments shall include review of the written risk assessment document and a determination of whether additional toxicity data exist that were not considered in the assessment. If additional toxicity data are identified that were not considered in the risk assessment, the risk assessment shall be updated in accordance with annex A, section A.4. The following shall be documented when utilizing an existing risk assessment: – – the source of the risk assessment; identification and discussion of any data not addressed by the assessment; and

– comparison and contrast of the existing risk assessment to the requirements of annex A, section A.4, with respect to selection of uncertainty factors or other assumptions. A.3.2 Substances regulated by USEPA or Health Canada

If a substance is regulated under the USEPA's National Primary Drinking Water Regulations and EPA has finalized a Maximum Contaminant Level (MCL) or other means of regulation such as a treatment technique (see annex A, section A.2.24), no additional collection of toxicological data shall be required prior to performance of the risk estimation (see annex A, section A.6.1). Where Health Canada has finalized a Maximum Allowable Concentration (MAC), no additional toxicological evaluation shall be required prior to performance of the risk estimation (see annex A, section A.6.1). Annex D contains a list of regulatory values (MCL or MAC) and their corresponding SPACs. This list includes consensus evaluation criteria for substances that are regulated by both countries. A.3.3 Substances regulated by other agencies

If a substance is regulated by agencies including the U. S. Food and Drug Administration (Code of Federal Regulations, Title 21 Food and Drug Regulations), or state, national, or international regulatory bodies other than those specified in annex A, section A.3.2, the relevance of the regulation to drinking water shall be evaluated. This evaluation shall include a review of the quantitative risk assessment that supports the regulation, and a determination of whether additional toxicity data exist that have not been considered in the current assessment. No additional collection of toxicological data shall be required when the regulation provides sufficient information for performance of the risk estimation (see annex A, section A.6.1). If additional toxicity data are identified that were not considered in the current risk assessment, a revised risk assessment incorporating those data shall be performed as indicated in annex A, sections A.4 and A.7. A.3.4 Evaluation of multiple published risk assessments

When multiple published assessments are available for a specific substance, the available assessments shall be reviewed and a rationale shall be provided for the selection of the assessment considered to be the most appropriate for the evaluation of human exposure through drinking water. Factors used to determine the appropriate assessment shall include, but not be limited to, the following:

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– – –

completeness and currency of the data review of each assessment; technical competence of the organization(s) that sponsored the assessment; and species and route(s) of exposure for which the assessment was performed.

When multiple published risk assessments are reviewed and are determined to be of equivalent quality, the following hierarchy shall be used to select the appropriate assessment, based on sponsoring organization: 1) USEPA; 2) Health Canada; 3) international bodies such as the World Health Organization (WHO) or the International Programme on Chemical Safety (IPCS); 4) European bodies such as the Drinking Water Inspectorate (DWI) and KIWA; or 5) entities such as other federal or state regulatory agencies, private corporations, industry associations, or individuals.

A.4
A.4.1

Data requirements for new or updated risk assessments
General requirements

For each substance requiring a new or updated risk assessment, toxicity data to be considered shall include, but not be limited to, assays of genetic toxicity, acute toxicity (1- to 14-d exposure), short-term toxicity (14- to 28-d exposure), subchronic toxicity (90-d exposure), reproductive toxicity, developmental toxicity, immunotoxicity, neurotoxicity, chronic toxicity (including carcinogenicity), and human data (clinical, epidemiological, or occupational) when available. For a fuller understanding of the toxic potential of the substance, supplemental studies shall be reviewed, including, but not limited to, mode or mechanism of action, pharmacokinetics, pharmacodynamics, sensitization, endocrine disruption, and other endpoints, as well as studies using routes of exposure other than ingestion. Structure activity relationships, physical and chemical properties, and any other chemical specific information relevant to the risk assessment shall also be reviewed. Toxicity testing shall be performed in accordance with the most recent adopted toxicity testing protocols such as those described by the Organization For Economic Cooperation and Development (OECD)14, U. S. Environmental Protection Agency (USEPA), and U. S. Food and Drug Administration (FDA)15. All studies shall be reviewed for compliance with Good Laboratory Practice (21 CFR, Pt 58/40 CFR, Pt 792).
NOTE – Review of the study according to the approach suggested in Klimisch et. al, 1997 may also be used to determine the quality of reported data.

A weight-of-evidence approach shall be employed in evaluating the results of the available toxicity data. This approach shall include considering the likelihood of hazard to human health and the conditions under which such a hazard may be expressed. A characterization of the expression of such effects shall also be included, as well as the consideration of the substance’s apparent mode of action. The quality and quantity of toxicity data available for the substance shall determine whether the evaluation is performed using a qualitative risk assessment approach (see annex A, section A.4.2) or a quantitative risk assessment approach (see annex A, section A.4.3).
14 15

Organization for Economic Cooperation and Development, 2 Rue André Pascal, F-75775, Paris Cedex 16, France U. S. Food and Drug Administration, 5600 Fishers Lane, Rockville, MD 20857

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A.4.2

Data requirements for qualitative risk assessment

Toxicity testing requirements for the qualitative risk assessment procedure are defined in annex A, table A1. A minimum data set consisting of a gene mutation assay and a chromosomal aberration assay shall be required for the performance of a qualitative risk assessment. Modifications in the specified toxicity testing requirements (inclusions or exclusions) shall be permitted when well supported by peer-reviewed scientific judgment and rationale.
NOTE – Modifications may include, but are not limited to, the following types of considerations: alternate assays of genetic toxicity, and supplemental toxicity studies other than those specified.

Required studies and available supplemental studies shall be reviewed in order to perform a qualitative risk estimation in accordance with annex A, section A.7.2. A.4.3 Data requirements for quantitative risk assessment

Toxicity testing requirements for the quantitative risk assessment procedure are defined in annex A, table A2. A minimum data set consisting of a gene mutation assay, a chromosomal aberration assay, and a subchronic toxicity study shall be required for the performance of a quantitative risk assessment. The required studies and preferred criteria are defined in annex A, table A2. Modifications to the minimum data set shall be permitted when well supported by peer-reviewed scientific judgment and rationale.
NOTE – Modifications may include, but are not limited to, acceptance of studies using alternate routes of exposure, alternate assays of genetic toxicity, and supplemental toxicity studies other than those specified.

Required studies, additional studies, and available supplemental studies shall be reviewed in order to perform a quantitative risk estimation in accordance with annex A, section A.7.3. Additional studies for the evaluation of reproductive and developmental toxicity (as specified in annex A, table A2) shall be required to be reviewed when: – results of the required minimum data set studies and any supplemental studies indicate toxicity to the reproductive or endocrine tissues of one or both sexes of experimental animals; or – the compound under evaluation is closely related to a known reproductive or developmental toxicant.

A.5

Data requirements for evaluating short-term exposures

Extractants from products used in contact with drinking water may be elevated initially but rapidly decline with continued product contact with water. Examples include, but are not limited to, solvent-containing coatings and solvent cements. Short-term exposure paradigms, appropriate for potentially high initial substance concentrations, shall be used to evaluate potential acute risk to human health of short-term exposures. The short-term exposure period shall be defined as the first 14 d of in-service life of the product. Sound scientific judgment shall be used to determine whether calculation of a Short-Term Exposure Level (STEL) is appropriate for a given contaminant. The NOAEL or LOAEL for the critical short-term hazard of the substance shall be identified. The following types of studies shall be considered for identification of short-term hazard: – short-term (less than 90 d duration) toxicity study in rodents or other appropriate species with a minimum 14-d post-treatment observation period, clinical observations, hematology and clinical chemistry, and gross pathology (preferably an oral study in rodents);

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– reproduction or developmental assays (for substances that have these endpoints as the critical effects); or – subchronic 90-d study in rodents or other species (preferably an oral study in rats).

The critical study shall be used to calculate a Short-Term Exposure Level (STEL) in accordance with annex A, section A.8. Selection of uncertainty factors for calculation of a STEL shall consider the quality and completeness of the database for assessing potential short-term effects. Selection of uncertainty factors shall also consider data that quantify interspecies and intraspecies variations. Other parameters that shall be considered in the determination of a STEL include identification of any sensitive subpopulations, the potential for adverse taste and odor, and solubility limitations at the calculated STEL. The STEL shall be calculated using assumptions to protect for a child’s exposure to the contaminant in the absence of data that demonstrate adults are more sensitive than children. In the absence of appropriate data to calculate a STEL, see annex A, section A.7.1.2.

A.6

Risk estimation for published assessments

Calculation of the SPAC is intended to account for the potential contribution of a single substance by multiple products or materials in the drinking water treatment and distribution system. In any given drinking water treatment and distribution system, a variety of products and materials may be added to, or may contact, the treated water prior to ingestion. The SPAC calculation is intended to ensure that the total contribution of a single substance from all potential sources in the drinking water treatment and distribution system does not exceed its acceptable concentration. A.6.1 SPAC calculation for regulated substances

To calculate the SPAC, an estimate of the number of potential sources of the substance from all products in the drinking water treatment and distribution system shall be determined. The SPAC shall be calculated as follows: SPAC (mg/L) = promulgated regulatory value (mg/L) estimated number of drinking water sources

In the absence of specific data regarding the number of potential sources of the substance in the drinking water treatment and distribution system, the SPAC shall be calculated as 10% of the promulgated regulatory value. A.6.2 SPAC calculation for other published risk assessments

Review of the risk assessment shall include evaluation of the risk estimation, if one is provided. If the existing risk estimation has been performed in a manner consistent with the procedures in annex A, section A.7.3 for non-carcinogenic or carcinogenic endpoints, the SPAC shall be calculated as follows: SPAC (mg/L) = estimated risk estimation (mg/L) estimated number of drinking water sources

In the absence of specific data regarding the number of potential sources of the substance in the drinking water treatment and distribution system, the SPAC shall be calculated as 10% of the existing risk estimation.

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If the existing risk estimation is not consistent with annex A, section A.7.3, or if a risk estimation is not provided, a TAC and SPAC shall be calculated for the substance according to the procedures in annex A, section A.7.3.

A.7

Risk estimation using new and updated risk assessments

The method of risk estimation used for new and updated risk assessments shall be determined by the quantity and quality of toxicity data identified for the contaminant of concern (see annex A, section A.4). When available toxicity data are insufficient to perform the qualitative or quantitative risk assessments, or when toxicity data are available but the normalized contaminant concentration does not exceed the applicable threshold of evaluation value, a threshold of evaluation shall be determined for the substance according to annex A, section A.7.1 if applicable. For all other data sets, the risk estimation shall be performed according to annex A, section A.7.2 or A.7.3. A.7.1 Threshold of evaluation

The following thresholds of evaluation shall be considered when available toxicity data do not meet the minimum requirements to perform a risk estimation using either the qualitative or quantitative approach. Application of the threshold of evaluation shall also be considered for the evaluation of normalized contaminant concentrations that do not have existing risk assessments and that do not exceed the defined threshold of evaluation concentrations. In this case, a qualitative review of the available data shall be performed to determine whether adverse health effects can result at the threshold of evaluation exposure concentrations defined in annex A, section A.7.1.1. A.7.1.1 Threshold of evaluation for chronic exposure Performance of a risk assessment shall not be required for an individual substance with a normalized concentration less than or equal to the following threshold of evaluation values: – static normalization conditions: toxicity testing shall not be required for an individual substance with a normalized concentration less than or equal to the threshold of evaluation value of 3 μg/L. – flowing normalization conditions: toxicity testing shall not be required for an individual substance with a normalized concentration less than or equal to the threshold of evaluation value of 0.3 μg/L. These threshold of evaluation values shall not apply to any substance for which available toxicity data and sound scientific judgement such as structure activity relationships indicate that an adverse health effect results at these exposure concentrations. A.7.1.2 Threshold of evaluation for short-term exposure If an appropriate short-term toxic effect is not identified by the available data, the initial (Day 1) laboratory concentration shall not exceed 10 μg/L. This threshold of evaluation value shall not apply to any chemical for which available toxicity data and sound scientific judgment such as structure activity relationships indicate that an adverse health effect can result at the 10 μg/L concentration upon short-term exposure to the chemical. A.7.2 TAC determination for qualitative risk assessment

TACs for qualitative risk assessments shall be determined as indicated in annex A, table A3.

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The procedure used to calculate the TAC for a new risk assessment (including qualitative assessments that are updated upon generation of new data) shall be determined by the toxicologic endpoint identified as the critical effect (see annex A, section A.2.3). For a substance with a non-carcinogenic endpoint, a TAC shall be calculated according to annex A, section A.7.3.1. For a substance with carcinogenic potential, a TAC shall be calculated according to annex A, section A.7.3.2. The minimum data set for the quantitative risk assessment (as defined in annex A, section A.4.3 and table A2) shall first be evaluated for genotoxic potential according to the requirements of annex A, table A3. Based on the review of genotoxic potential, the need for supplemental studies or chronic toxicity and carcinogenesis data shall be determined. A.7.3.1 Assessment of noncarcinogenic endpoints For noncarcinogenic endpoints, the TAC shall be calculated using either the NOAEL/LOAEL procedure outlined in annex A, section A.7.3.1.1, or the benchmark dose (BMD) procedure outlined in annex A, section A.7.3.1.2, as appropriate. The rationale for the selection of the procedure shall be provided in the assessment.
NOTE – Selection of the appropriate TAC calculation procedure will depend on the characteristics of the data set identified for the substance. Simple data sets consisting of a small number of studies may be best evaluated using the procedure in annex A, section A.7.3.1.1. Complex data sets consisting of several studies, or involving reproduction or developmental endpoints, may be best evaluated using the benchmark dose procedure in annex A, section A.7.3.1.2. The appropriateness of the fit of the data to the BMD shall also be considered.

A.7.3.1.1

NOAEL or LOAEL approach

The substance data set shall be reviewed in its entirety, and the highest NOAEL for the most appropriate test species, relevant route of exposure, study duration, mechanism, tissue response, and toxicological endpoint shall be identified. If an NOAEL cannot be clearly defined from the data, the lowest LOAEL for the most appropriate test species, relevant route of exposure, and toxicological endpoint shall be utilized. The general procedure for calculating the TAC using this approach is as follows: a) Determine the critical study and effect from which the NOAEL or LOAEL will be identified according to the following hierarchy (USEPA, 1993 and Dourson et al., 1994): 1) adequate studies in humans; 2) adequate studies in animal models most biologically relevant to humans (e. g., primates), or that demonstrate similar pharmacokinetics to humans; 3) adequate studies in the most sensitive animal species (the species showing an adverse effect at the lowest administered dose using an appropriate vehicle, an adequate study duration, and a relevant route of exposure); and 4) effects that are biologically relevant to humans. b) Calculate the reference dose (RfD) according to the following equation (based on USEPA, 1993): RfD NOAEL or LOAEL (mg/kg/day) x (mg/kg/day) UF x number of days dosed per week 7 days

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NOTE – When other than daily dosing was used in the critical study, the RfD calculation shall be adjusted to reflect a daily dosing schedule.

c) Calculate the TAC based on the RfD with adjustment for significant contribution(s) of the substance from sources other than drinking water according to the following equation: TAC = (mg/L) where: NOAEL = Highest NOAEL for the critical effect in the most appropriate species identified after review of data set. If an NOAEL is not defined, the LOAEL shall be used with a corresponding adjustment in the uncertainty factor (see annex A, table A4); BW = Assumed body weight of individual to be protected in kg (generally 10 kg for a child and 70 kg for an adult); UF = Uncertainty factor (total) based upon the applicability of the test data in extrapolating to actual conditions of human exposure (see annex A, table A4). These are often referred to as safety factors; and DWI = Drinking Water Intake: the assumed average daily drinking water consumption per day (generally 1 L for a child and 2 L for an adult).
NOTE 1 – In the absence of data to determine the drinking water contribution of a substance, a default drinking water contribution of 20% shall be applied (USEPA, 1991). NOTE 2 – If calculation of the non-drinking water contribution of a substance exceeds the value of the (RfD x BW), verify that all potential exposures to the substance in the critical study have been accounted, e. g., whether the substance present as a contaminant in the feed as well as dosed into the drinking water.

[RfD (mg/kg/day) x BW (kg)] - [total contribution of other sources (mg/day)] DWI (L/day)

A.7.3.1.2

Benchmark dose approach

The benchmark dose level (BMDL) for the substance shall be calculated by modeling the substance’s dose response curve for the critical effect in the region of observed responses. The benchmark response (BMR) concentration shall be determined by whether the critical response is a continuous endpoint measurement or a quantal endpoint measurement. The BMR shall be calculated at the 10% response level. The general procedure for calculating the TAC using the BMDL is as follows: a) Calculate the reference dose (RfD) according to the following equation: BMDL (mg/kg/day) number of days dosed per week RfD = x (mg/kg/day) 7 days UF
NOTE – When other than daily dosing was used in the critical study, the RfD calculation shall be adjusted to reflect a daily dosing schedule.

b) Calculate the TAC based on the RfD with adjustment for significant contribution(s) of the substance from sources other than water according to the following equation: TAC (mg/L) = [RfD (mg/kg/day) x BW (kg)] - [total contribution of other sources (mg/day)] DWI (L/day)

A10

? 2007 NSF where:

NSF/ANSI 61 – 2007

BMDL = The lower confidence limit on the dose that produces a specified magnitude of change (10%) in a specified adverse response (BMD10); BW = Assumed body weight of individual to be protected in kg (generally 10 kg for a child, and 70 kg for an adult); UF = Uncertainty factor (total) based upon the applicability of the test data in extrapolating to actual conditions of human exposure (see annex A, table A4). These are often referred to as safety factors; and DWI = Drinking Water Intake: the assumed average daily drinking water consumption per day (generally 1 L for a child and 2 L for an adult).
NOTE 1 – In the absence of data to determine the drinking water contribution of a substance, a default drinking water contribution of 20% shall be applied (USEPA, 1991). NOTE 2 – If calculation of the non-drinking water contribution of a substance exceeds the value of the (RfD x BW), verify that all potential exposures to the substance in the critical study have been accounted, e. g., whether the substance is present as a contaminant i

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