NSF 61 was developed to establish minimum requirements for contaminants that leach into drinking water from products that make up the drinking water system. Products can be evaluated to the Standard by an ANSI accredited Certifying Agency.
The testing process includes an audit of the manufacturing process, and facility, toxicological evaluation, product testing, and a Report that provides the test results. Once the product is determined to be in compliance with the Standard it may then bear the mark of the Certifying Agency showing compliance to NSF 61. The process is started by submitting information such as wetted parts list, mechanical drawings, use instructions, etc. is submitted to the Certifying Agency.
The Certifying Agency reviews the information, conducts an audit of the manufacturing location, and contacts the manufacturer of each wetted part of the product to obtain its chemical composition. The chemical composition information, and other pertient product information is submitted to a toxicologist for review. Using the information from the toxicologist, and requirements outlined in NSF 61, a specific testing program for the product is developed. The testing program starts by "conditioning" and "exposing" the product to pH specific extraction water.
The length of time for the exposure and conditioning process is dependent upon the type of product being tested. Once the conditioning and exposure process has been completed, the pH specific water, or "extraction water" is collected and analyzed for contaminants. These test results are "normalized" to account for any differences from the laboratory testing to actual field usage (e.g. surface are). These normalized test results are compared to the requirements outlined in Annex D and E of NSF 61. If all requirements have been met, and all contaminant concentrations are at or below the applicable limits, then the product is determined to be in compliance with NSF 61.
The product is then eligible to be "marked" with the Certifying Agencies mark showing compliance to NSF 61. Continued compliance of the product to NSF 61 is ensure by routine follow up testing, and audits at the manufacturing location.
2011, Karis Ray