Frequently Asked Questions

General Questions on NSF/ANSI Standard 61
Processed and Fabricated Products
NSF/ANSI Standard 61 and Lead
Stainless Steel Products and NSF Standard 61

General Questions on NSF/ANSI Standard 61

What is NSF/ANSI Standard 61?

NSF/ANSI Standard 61 - Drinking Water System Components was published in 1988 to establish minimum requirements for the control of potential adverse human health effects from products that contact drinking water.

NSF/ANSI Standard 61 includes criteria for testing and evaluating products to ensure they do not leach contaminants into the water that would be a health concern. These contaminants include those regulated by the United States Environmental Protection Agency (USEPA) and Health Canada, as well as any other non-regulated compounds that may be of concern.
What products are covered under NSF/ANSI Standard 61?
- Pipes and Related Products (including pipe, hose, fittings)
- Protective and Barrier Materials (including cements/coatings)
- Joining and Sealing Materials (including gaskets, adhesives, lubricants)
- Process Media (including carbon, sand, zeolite, ion exchange media)
- Mechanical Devices (including water meters, in-line valves, filters, process equipment)
- Mechanical Plumbing Devices (faucets, drinking fountains, and components)
- Potable Water Materials (including non-metallic materials, and ‘lead-free’ copper alloys)
What is involved in the NSF/ANSI Standard 61 Certification process?

The NSF Certification process has seven basic steps, as follows:
1. Application - NSF/ANSI Standard 61 requires a disclosure by the manufacturer of all water contact materials in the product and a disclosure by the manufacturer's material suppliers of all chemical ingredients in the materials.
2. Formulation, toxicology and product use information - Client and suppliers complete and submit NSF's Product Information Form. This provides formulation, toxicology and product use information.
3. NSF formulation review - NSF toxicologists perform a formulation review for each water contact material to determine any possible ingredients, contaminants, or reaction by-products that may potentially leach from the material into drinking water. This formulation review then determines the battery of chemical analyses that will be performed on a particular material.
4. Plant audit and sample collection - NSF then conducts an inspection of the production facility to verify the product formulation and production process and to ensure adequate quality control procedures are in place to prevent the use of unauthorized materials. Product samples are collected during the inspection and sent to NSF laboratories to be tested to the appropriate exposure protocol of NSF/ANSI Standard 61.
5. Laboratory testing - Devices or materials are evaluated according to the exposure and analysis methods in Annex B of NSF/ANSI Standard 61. Most products undergo a 3-week exposure process where the products are exposed to various formulated waters designed to extract specific types of contaminants. Contaminant concentrations are determined from chemical analyses of the exposure water samples.
6. Toxicology evaluation - These contaminant concentrations are then evaluated by a toxicologist to the pass/fail criteria in Annex D and E of NSF/ANSI Standard 61. Products that meet the requirements of the standard are then certified and appear in the NSF Listings. If products fail to meet the requirements of the standard, the manufacturer may identify the source of the failure and resubmit a reformulated product for certification.
7. Certification granted
  
  Follow-up program - Once products are certified and listed by NSF they are inspected and reviewed on an annual basis.
  
  Listed production facilities are then subjected to unannounced annual inspections by NSF auditors to ensure that certified products are made according to the authorized formulations and processes. Products are collected on a routine basis (typically once annually) for retesting.
  
  Occasionally, certified products will fail an annual retest. When this happens, NSF immediately notifies the manufacturer. NSF requires the manufacturer to stop shipment of noncompliant product and to fully investigate the cause of the failure. An NSF field auditor inspects the facility to ensure the manufacturer has taken these steps. If the manufacturer is able to identify and correct the cause of the failure, they may resubmit the product for certification. If the reformulated product meets the requirements of NSF/ANSI Standard 61, the manufacturer may again mark and sell the products as NSF certified.
How was NSF/ANSI Standard 61 developed? How is it maintained?

NSF/ANSI Standard 61 is overseen by the NSF Drinking Water Additives Joint Committee. This committee has a balance of 1/3 public health regulatory members, 1/3 product manufacturer members, and 1/3 product user representatives. Any proposal to revise the standard is typically assigned to a task group composed of joint committee members and external experts. Task group members are assigned by the chairman of the joint committee.

One standing group is the Health Advisory Board. This group consists of toxicologists from USEPA, Health Canada, state and provincial agencies, as well as toxicologists from industry, and private consulting firms. This group is responsible for reviewing and approving all allowable contaminant concentrations that are published in NSF/ANSI Standard 61.

Any revision that is proposed by a task group must receive majority approval from the joint committee. Any negative ballots from the joint committee must be circulated to all committee members and adjudicated, according to the guidelines of the American National Standards Institute (ANSI).

Once a revision is approved by the joint committee, the proposal passes to the NSF Council of Public Health Consultants, which consists of regulatory officials from public health agencies across North America.

Revisions to NSF/ANSI Standard 61 are also circulated for public comment and any concerns addressed through the guidelines of the American National Standards Institute. ANSI gives final approval to each revision of the standard.

Anyone may submit a proposed change to the standard, as well as other issues for discussion by the joint committee, by submitting an issue paper to the chairman of the joint committee. All meetings of the joint committee are open and may be attended by requesting an invitation from the secretary of the joint committee. Contact standards@nsf.org for further information.

If you have additional questions relating to NSF/ANSI Standard 61, or NSF's certification services, contact Dave Purkiss at 734.827.6855 or purkiss@nsf.org.

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Processed and Fabricated Products

Do certified products retain their NSF 61 certification if they are processed or fabricated and resold?

Many companies purchase NSF 61 certified products which are then reprocessed in some manner and resold. These processed or fabricated products do not retain their NSF Certification to NSF 61 unless the facility has an official NSF 61 Listing for the processed or fabricated product.
Example: Fabricated Pipe

A fabrication facility may purchase NSF 61 certified ductile iron pipe and fabricate grooved or flanged pipe and resell the product to a contractor or water utility. The product only retains the NSF 61 Certification if the fabrication facility has a NSF 61 listing for the grooved or flanged pipe. The certification denotes that the fabrication facility is inspected annually and has products periodically retested to confirm the fact that it is using NSF 61 certified pipe, that it has controlled sources of materials used for fittings and welding, and also ensure that any additional coating materials or processing aids are not going to add harmful contaminants to drinking water.

Example: Regenerated and reactivated media

Several process media companies now offer to take spent media from a water utility and regenerate or reactivate the media and then resell it to the water utility at a much lower cost than virgin media. How does the utility know that the media it is receiving back is the same media that they originally sent to the regeneration facility? How can the water utility be assured that the regenerated media conforms to NSF 61 and will not add harmful contaminants to drinking water? NSF 61 contains specific requirements for products and facilities that regenerate and reactivate media. Regenerated or reactivated media is not NSF 61 Certified unless the regeneration or reactivation facility has a NSF 61 Listing for the products.

Example: Repackaged process media

The same rule would apply to companies that are simply repackaging process media or other products. Even if a company is repackaging NSF 61 certified activated carbon, the NSF 61 certification is not maintained if it has not been separately certified for the repackaging company. How can a utility be sure that a company is only repackaging NSF 61 media and not substituting or mixing with some lower cost material that is not certified? Contamination control is another concern addressed by third party certification. If the repackaging facility has been separately certified then the water utility can be reassured that the facility is receiving unannounced annual inspections from NSF to verify the sources and certification of the media that is being packaged.
While a reprocessed or fabricated NSF 61 certified product does not retain its certification, it is still beneficial for manufacturers to choose NSF 61 certified materials for their end product. Choosing NSF 61 certified components or materials will save your company time and expenses when undergoing certification for your product.

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NSF/ANSI Standard 61 and Lead

What are the requirements for NSF/ANSI Standard 61 and lead?

NSF/ANSI Standard 61 contains requirements that both restrict the level of lead that can be contained in the water contact materials of drinking water products as well as the level of lead that can extract out.

Lead content requirements:
- Restriction on the use of lead containing materials: Section 3.5 of NSF/ANSI 61 precludes the use of lead as an intentional additive in wetted materials and components of products with the exception of brass and bronze meeting the definition of ‘lead free’ within the specific provision of the US Safe Drinking Water Act (SDWA). Through 2013, this has been applied under NSF/ANSI 61 as brass or bronze containing no more than 8% lead. Products are also required to comply with all chemical extraction requirements of NSF/ANSI 61, including lead.
  
  In 2011, US federal legislation passed that revised the definition of ‘lead free’ within the SDWA. In brief, the definition now requires that the wetted surfaces of pipes, pipe fittings, plumbing fittings, and fixtures meet a weighted average lead content of no more than 0.25%. The changes in the SDWA are set to take effect January 4, 2014. See this link for the enacted language. As Section 3.5 of NSF/ANSI 61 requires that products comply with the lead-free requirements of the SDWA, all NSF/ANSI 61 products falling into the scope of the legislation are also required to comply with the new 0.25% maximum lead content requirement. The date of this required compliance under NSF/ANSI 61 is the same as the date effective in the SDWA, January 4, 2014.
- Annex G: NSF/ANSI Standard 61 was revised in December 2008 to establish requirements for use when a 0.25% lead content requirement needs to be met in addition to current chemical extraction requirements of the standard. The requirements were placed in Annex G - Weighted Average Lead Content Evaluation Procedure to a 0.25% Lead Requirement. A request was made to add these requirements to the standard to allow manufacturers the option of being certified to a lead content standard, such as California's Health & Safety Code (Section 116875) commonly known as AB1953. That law, which went into effect January 1, 2010, applies to any pipe, pipe of plumbing fitting, or fixture intended to convey or dispense water for human consumption through drinking or cooking. Similar laws have since been enacted in Vermont, Maryland, Louisiana, and is now set to take effect nationally through the revised US SDWA in 2014.
  
  In 2010, the lead content evaluation procedures of Annex G were moved to NSF/ANSI 372 and Annex G updated to simply reference it. Movement of the procedures from Annex G to 372 allowed for their application on products beyond the scope of NSF/ANSI 61 like drinking water treatment units and food service equipment. It also allowed for citing compliance separate from NSF/ANSI 61 for those jurisdictions wishing to do so.
  
  At the same time Annex G procedures were moved to NSF/ANSI 372, the annex was balloted to be retired three years following. The end of that three year period is October 2013. Although Annex G will be retired from NSF/ANSI 61, NSF will continue to support the ‘-G’ certification marks as long as they are of value. This is anticipated to be for a number of years as they provide a simple mechanism of denoting compliance with both the chemical extraction requirements of NSF/ANSI 61 as well the new ‘lead free’ requirements of US State and Federal law.
  
  Currently, all products certified by NSF as compliant with Annex G are also compliant with NSF 372. No additional testing is required beyond the normal routine monitoring of certified products is required. The listings of products currently certified by NSF to Annex G will continue to bear the [G] certification footnote:
```
    [Current footnote]
    [G] Product complies with NSF/ANSI 61 Annex G, NSF/ANSI 372 and conforms with lead content
        requirements for “lead free” plumbing as defined by California, Vermont, Maryland, and
        Louisiana state laws and the U.S. Safe Drinking Water Act due to take effect January
        2014.
    
    [Future footnote]
    [G] Product complies with NSF/ANSI 372 and conforms with lead content requirements for 
        “lead free” plumbing as defined by California, Vermont, Maryland, and Louisiana state 
        laws and the U.S. Safe Drinking Water Act in effect as of January 4, 2014.
```
Lead extraction requirements:
- NSF/ANSI Standard 61 requires all metallic products and components to be evaluated for the leaching of lead as well as other metal contaminants. Metallic pipe, fittings, valves, and other mechanical devices are all tested with two specially formulated waters. One is pH 5 and another pH 10. The pH 5 test water is especially aggressive for copper, chromium, nickel, and antimony. The pH 10 test water is especially aggressive for lead, arsenic, barium, beryllium, boron, cadmium, mercury, selenium, and thallium. Products are exposed to these test waters for 16 days where the device is filled with fresh test water each day. On the 17th day water is held in the device for 16 hours. The resulting contaminant concentrations are analyzed and mathematically normalized to reflect the concentrations expected from actual product when it is installed in the field. These normalized concentrations are then compared to the pass/fail results of NSF/ANSI Standard 61, which is 5 ppb for lead.
  
  Faucets, drinking fountains, and endpoint devices that dispense drinking water are tested and evaluated in a different manner. NSF/ANSI Standard 61 requires that these products be tested over a 19 day time period using a specially formulated pH 8 test water. Samples for lead are taken at 9 sample days throughout the 19 day test. Other metal contaminants are measured on the last day of the test. A minimum of 3 devices must be tested for lead and a statistical calculation is made based on the geometric mean of the lead leach concentrations, the standard deviation of the concentrations and a probability factor which is based on the number of products tested. A statistical Q value is derived from this calculation to represent the lead dose of the product. An endpoint device must have a Q value less than or equal to 5 ug for endpoint devices and 3 ug for stop valves and flexible connectors.
- Annex F (Revisions to the evaluation of lead): In 2006 the DWA Lead Task Group developed proposed changes designed to increase the public health protection of the Standard relative to the evaluation of lead leaching. The requirements were approved by the Drinking Water Additives Joint Committee for inclusion in the Standard as normative requirements effective July 1, 2012. Details of the revisions were maintained in Annex F of the 2007a through 2011 versions of the standard and include:
  - reduction of the TAC for lead from 15 µg/L to 5 µg/L;
  - reduction of the SPAC for lead from 1.5 µg/l to 0.5 µg/L;
  - reduction of Q (&R) Statistic criteria from 11 to 5 for all section 9 devices other than supply stops, flexible plumbing connectors, and miscellaneous components; and
  - reduction of Q (&R) Statistic criteria from 11 to 3 for than supply stops, flexible plumbing connectors, and miscellaneous components.
  Given the impact of those changes, the joint committee established a 5-year implementation period. The 5-year implementation period ended July 1, 2012. At that time, the requirements held in abeyance in Annex F were moved into the main body of the standard and enacted. At NSF, all NSF certified products not compliant with the reduced extraction criteria by that time were removed from listings. All NSF certified products have met (and continue to meet) the lower criteria of the standard.
Implementation of the 2014 changes to the US Safe Drinking Water Act:

In 2011, US federal legislation passed that revised the definition of ‘lead free’ within the US Safe Drinking Water Act (SDWA). In brief, the definition now requires that the wetted surfaces of pipes, pipe fittings, plumbing fittings, and fixtures meet a weighted average lead content of no more than 0.25%. The changes in the SDWA are set to take effect January 4, 2014. See this link for the enacted language. As Section 3.5 of NSF/ANSI 61 requires that products comply with the lead-free requirements of the SDWA, all NSF/ANSI 61 products falling into the scope of the legislation are also required to comply with the new 0.25% maximum lead content requirement. The date of this required compliance under NSF/ANSI 61 is the same as the date effective in the SDWA, January 4, 2014.

NSF Certified companies are requested to review their listings closely to assure products they desire to retain in listing after the implementation date (January 4, 2014) are complaint with the new low lead requirements. Non-compliant products will be removed from NSF 61 listings by that date. Evaluations to NSF/ANSI 61 Annex G and NSF/ANSI 372 demonstrate compliance with the new lead free definitions. In addition, no response is required by certified manufacturers of process media and coatings as those products have already been screened to a no-lead criteria.

Companies who have not had their products evaluated to the new lead content criteria are asked to contact their NSF certification project manager and confirm how they wish to proceed. Options include:
1. Advise that the product doesn’t meet the new lead free definition and request decertification of the product prior to January 4, 2014.
2. Request verification of compliance against NSF/ANSI 372. Products complying with this option will be eligible for use of the ‘-G’ certification marks as well as the [G] listing footnote attesting compliance (footnote language above).
3. Identify the product as a type specifically exempted from compliance with the lead free requirements of the law and request it be noted as such in the product certification. Specifically exempted potable water products include main gate valves ≥ 2” and service saddles. Selection of the exempted status under NSF’s standard 61 listings will result in the listing footnoted to indicate the weighted average lead content of the product may be in excess of 0.25%.
4. Identify the product as a type specifically exempted from being evaluated to the requirement as currently allowed under the last two bullet points in Section 3.5 of the standard. This doesn’t infer that the products are not required to comply with the requirements of the law or their components of construction, rather that the NSF certification to NSF/ANSI 61 will not have verified compliance with it. The main items covered under this option are Non-POE (point-of-entry) and non-POU (point–of-use) water treatment equipment such as municipal filtration devices (e.g. microfiltration, ultrafiltration, nanofiltration, reverse osmosis, etc.), chemical feeders, disinfection generators (e.g. chlorine dioxide, hypochlorite, ozone ultraviolet, etc.) and electrodialysis technologies.
NSF/ANSI Standard 372

NSF/ANSI 372 Drinking water system components - Lead Content is the third in a series of standards developed by the NSF Joint Committees on Drinking Water Additives. The other two Standards for drinking water additives products are NSF/ANSI 60 Drinking water treatment chemicals - Health effects, which addresses drinking water treatment chemicals (also known as direct additives) and NSF/ANSI 61 Drinking water system components - Health effects, which covers products and materials that contact drinking water (also known as indirect additives).

Prior to being developed as NSF/ANSI 372, part of the content of this Standard was established as NSF/ANSI 61, Annex G - Weighed average lead content evaluation procedure to a 0.25% lead requirement. Annex G was developed by the NSF Drinking Water Additives Task Group on Lead and approved by the NSF Joint Committee on Drinking Water Additives – System Components for addition to NSF/ANSI 61 in 2008. The impetus for creating Annex G was the promulgation of individual state regulatory requirements limiting the amount of lead that may be contained in products contacting drinking water. While Annex G was an optional evaluation method within NSF/ANSI 61, it required that products also meet the chemical extraction requirements of NSF/ANSI 61, and it was limited in application to drinking water products that were included within the Scope of ANSI/NSF 61. The NSF Joint Committee on Drinking Water Additives – System Components determined that creation of a separate standard addressing lead content requirements would provide greater flexibility in the application of the lead content requirements to the marketplace and to organizations seeking to reference such requirements. Highlights include:
- The annex contains <0.25% weighted average lead content requirements. Compliance is determined by a weighted average calculation involving the maximum percent lead content of material specifications and wetted surface areas.
- Does not consider coatings or acid washing. Compliance is determined by the maximum percent lead content of material specification for each component prior to application of any coatings or lead wash treatments.
- For internally threaded products, the wetted surface area includes 25 percent of the threaded area(s). This is consistent with the assumptions used in the rest of Standard 61.
- Defines a test methodology for the analytical verification of the lead content of materials and minimum requirements for its use.
For questions or concerns regarding the evaluation of lead under NSF/ANSI 61 or NSF/ANSI 372, please contact Pete Greiner at (+1) 734.769.5517 or greinerp@nsf.org.
Does NSF/ANSI Standard 61 only test for lead?

No, NSF tests for other metallic contaminants as well as nonmetallic contaminants. In fact, the standard requires a full formulation disclosure of all chemical ingredients in each water contact material. The standard then requires testing for any chemical contaminant that might possibly leach from each material into drinking water.
Can a pure lead device pass NSF/ANSI Standard 61?

No. This misconception started when an article reported that a small lead device was tested to the NSF/ANSI Standard 61 test protocol and it passed for lead. A close reading of the article shows that the lead device was only tested with the pH 5 test water. It was not tested with the pH 10 test water, which is required by the standard. The same article claims that other devices were tested with both the pH 5 and pH 10 test waters and showed that the pH 10 test water was 71 times more aggressive for lead leaching than the pH 5 test water. If the factor of 71 was applied to the pH 5 test results for the small lead device, it would have clearly failed to meet the standard. In fact, many brass products containing only small amounts of lead have difficulty meeting the testing requirements of NSF/ANSI Standard 61.
How can I be sure that the faucet or plumbing device meets the NSF Standard?

Products certified against the NSF Standard carry a certification mark of the certifying organization. NSF International publishes listing books of products that it has tested and certified against the NSF Standard. NSF International also maintains these listings through its Internet site. One can obtain Listing books from NSF International at 1-800-NSF-MARK (800-673-6275), or visit its website at www.nsf.org.
Which parties helped develop the NSF Standard?

The standard was developed using voluntary consensus process. All interested parties were represented, including regulatory agencies, industry, water suppliers, consultants, and other users of products covered by the standard.
Is NSF the only organization that can test against the Standard?

Any organization that is accredited by the American National Standards Institute to certify products against NSF Standard 61 can test products against the NSF Standard. Currently 44 states have regulations requiring products to meet NSF Standard 61 and all of these states require products to be certified by an ANSI-accredited certifier.

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Stainless Steel Products and NSF Standard 61

What is stainless steel?

Stainless steel, compared to typical steel, is a general class of metal alloys that contains lower levels of iron and higher levels of chromium, vanadium, etc. The actual percent of the various elements yield different physical properties.
Why do people use stainless steel products with drinking water systems?

In general, stainless steels are quite hard, tough, and corrosion resistant in comparison to some other materials used in drinking water applications.
Are all stainless steel products compliant with NSF Standard 61.

No. Only products that are certified to NSF/ANSI Standard 61 can be assumed to meet the requirements of NSF/ANSI Standard 61. Certification to NSF/ANSI Standard 61 includes product testing and production location auditing to ensure ongoing compliance with the health based requirements of NSF 61. This includes testing products on an annual basis, by exposing them to different formulated waters (typically at pH 5, pH 8 and pH 10) and testing for regulated metals such as antimony, arsenic, barium, cadmium, chromium (including chromium VI), copper, lead, mercury, selenium, thallium, and nickel, as well as any other inorganic and organic leachate concerns that may derive from cutting oils, lubricants, process aids, welding, machining, and other forming by-products. The certification process also includes annual unannounced inspections of the manufacturing facility to verify that the manufacturer is making the product using the same raw materials, material suppliers and production process as the products that are tested.
I thought because stainless steel was listed in Annex C of NSF 61 that all stainless products meet the requirements of the standard?

Annex C of NSF 61 provides a list of materials that have been extensively tested under certain conditions, which then can reduce the amount of testing that NSF needs to perform when certifying products to NSF 61. For example several grades of stainless steel have been listed under Annex C at specific surface area to volume ratios and at certain temperatures (23°C and 30°C). When product manufacturers use these materials in their products under these conditions, NSF may not have to do as much testing as we would if they were using other materials. However NSF would still need to audit the manufacturing facility to verify that these materials are being used in certified products, and testing would be required if other materials are in the products, or if the stainless steel is being used at higher temperatures such as domestic (60°C) or commercial (82°C) hot water.
I need NSF Standard 61 Certified stainless steel pipe and fittings. Where do I find them?

Use the NSF web-based Standard 61 Certified Potable Water System search engine.

From the NSF website you may choose from many search criteria such as:
- Manufacturer name, if you know the maker of the product
- Product trade name, if you know the tradename or model number, etc.
- Manufacturing location, if you seek product from a certain country, state, etc.
- Product type, if you need a particular item like pipe, valve, fitting, pump, etc.
- Material type, if you need a specific material such as SS, PVC, PE, Cu, brass, etc.
If I can't find the specific company/product type I seek, what should I do?

Contact NSF staff for assistance. Have details of your target products and preferred suppliers. NSF staff may be able to help you find the NSF 61 Certified products you seek. NSF can also help you by networking with your preferred suppliers and rapidly arranging the appropriate evaluation of products you need to meet bid specifications and drinking water safety requirements.
Why do companies get NSF Standard 61 Certified for stainless steel products?

Most US States and Canadian Provinces have regulations or policies that require public drinking water system components to comply or be certified to NSF Standard 61. In addition most of the plumbing codes across the US also require products to be certified to NSF 61. While enforcement of these requirements varies greatly by region, these requirements have resulted in a growing number of specifications for NSF 61 for stainless steel and other potable water products.

Make sure the products you buy are NSF Certified!

If you have additional questions relating to NSF/ANSI Standard 61 and stainless steel or NSF's certification services, contact Dave Purkiss at 734-827-6855 or purkiss@nsf.org.

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