There are many laws and standards that regulate potable water systems, but chief among them is the Safe Drinking Water Act (SDWA), along with the Reduction in Lead in Drinking Water Act. These laws created new regulations around all material used in potable water systems, particularly affecting brass alloy fittings. The SDWA essentially adopted the standards created by the National Sanitation Foundation (NSF), particularly NSF 61. This standard is now critically important for any fitting and piping, including valves used in potable water systems. But what exactly is NSF 61? Is certification legally required for valves used in potable water systems? Is NSF 61 followed by most countries in the world? These are all important questions, and their answers are a little bit complicated.
NSF/ANSI 61
This standard ensures there are minimal health effects from chemicals and contaminants that can leach into the water from any material that is in contact with the water. NSF 61, when it was first published in 1989, was more stringent than previous standards, as it lowered the “acceptable” concentrations of contaminants greatly. While NSF 61 impacted brass alloy fittings the most, the standard covers any material that can contact potable water, from polyvinyl chloride (PVC) to concrete. It covers fittings, O-rings, flux, coatings and so on. This standard was endorsed by the American National Standards Institute (ANSI) and is now referred to as NSF/ANSI 61.
A potable water fitting—a valve, for example—can be certified to the NSF/ANSI 61. This involves sending a sample of valves to a certified third-party laboratory, such as Underwriters Laboratories. The valves are then tested and analyzed according to the materials they have and the corresponding possible leachate. For instance, a brass valve has its material composition analyzed for toxic metals (and metalloids) like arsenic, cadmium and lead. A PVC valve is tested for other contaminants like unreacted vinyl chloride residue.
Once the tests are complete, the valve is either certified or refused based on the results. It is not a given that a manufactured valve will pass this certification as NSF reports that around 17% of tested products actually do not qualify. Once certified, the NSF 61 approval stamp lasts for five years before renewal.
Is NSF 61 certification required for a valve to be installed in a potable water system? The answer is no, or at least, it is not explicitly required. First off, the SDWA applies to public water works and commercial buildings, and secondly, the SDWA only requires valves to be “lead free” and to contain no contaminants. A manufacturer can prove this from their own quality assurance program. However, almost all public works require NSF 61 certified valves, and many companies embrace this standard as it makes it easy and compelling to prove compliance with the
SDWA regulations.
NSF/ANSI 372
While NSF 61 addresses leaching, including lead, NSF 372 addresses the allowable lead content of a substance that contacts potable water. This can be fittings, like valves, but also traditional lead-containing substances like flux. Specifically, NSF 372 requires valves have an average maximum of 0.25% lead in the wetted surfaces. This does mean certain parts of the valves can contain lead, and the valve will still qualify as “lead free.” It is a complicated standard even manufacturers can misunderstand or fail to meet, and NSF 372 certification ensures the valve does not violate the Reduction of Lead in Drinking Water Act.
International Equivalents
An NSF 61 certification in the United States is the gold standard, but this is not exactly the same internationally. Most other countries use their own laws and regulations for testing. The NSF also offers certifications for various European standards as well. The following examples of international equivalents are not an exhaustive list but do shed light on the approval process for potable water systems around the world.
Australian WaterMark Certification Level 1
This is the Australian equivalent to NSF 61 and is represented as “WaterMark” on products. It also requires third-party testing by a certified laboratory. Presently, Australia has different standards on permissible lead concentrations, though they will require the same 0.25% concentration after May 2026.
French (ACS) & Germany (KTW) Regulations
France and Germany are both in the European Union (EU). Therefore, manufacturers of both countries often use EU standards. EN 15664 and EN 12873 outline procedures for testing materials to ensure there is no toxic leachate.
Manufacturers can declare their conformity to EU standards such as these with the Conformité Européenne (CE) mark, but this is not a certification as it does not require a third-party test. Both France and Germany have laws in their respective countries that establish regulations and a certification process. For the French, those are the Attestation De Conformité Sanitaire (ACS) regulations. In 2019, Germany established its KTW certification.
Britain’s WRAS
The United Kingdom uses its Water Regulations Advisory Scheme (WRAS) to approve products for use in potable water systems. The WRAS draws on applicable European standards (ENs) and International Organization for Standardization (ISO) standards in a thorough certification process that incorporates a wide range
of criteria.
Navigating laws, regulations and standards can be a confusing and frustrating part of a project. This article covered the main standard—NSF/ANSI 61—that applies to potable water systems. There is much more to the NSF 61 standard and a lot greater depth in all the mentioned international equivalents, but hopefully this article shed some light on the required approvals for potable water applications.