Residential Drinking Water Treatment Protocols


We have the unique ability to develop new protocols for testing and certification based on our customer’s needs. Much like traditional NSF standards, protocols are developed through a collaborative process involving a technical panel, including the product manufacturer, regulators, academicians, end users and public health experts with relevant expertise. Unlike NSF standards, however, the development phase is confidential, protecting your proprietary interests.

By creating customized testing criteria and validating performance and product claims, we provide assurance of product performance to your customers in your desired markets.

To learn more about these protocols or to get started with certification, please contact


NSF P473: Drinking Water Treatment Units – PFOS & PFOA

NSF P473 provides manufacturers of point-of-use carbon based and reverse osmosis drinking water treatment technologies with the opportunity to validate reduction claims associated with the emerging contaminants, perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS).

PFOA and PFOS have been widely used in industrial and consumer applications such as non-stick cooking surfaces, paper and cardboard food packaging, insecticides, electronics, stain repellants, paints, plumbing tape and firefighting foam. Recognized as a risk to human health, the U.S. Environmental Protection Agency (EPA) has stated that a new lifetime of exposure health advisory has been established at 70 parts per trillion (ppt) for both PFOA and PFOS in drinking water. This EPA health advisory level was established to provide a margin of protection to all Americans as well as those who are immuno-compromised or in special populations (elderly, children).

Manufacturers, health officials and regulators have recognized the importance of reducing PFOS and PFOA in drinking water, after epidemiological studies of workers exposed to high levels of the contaminants were reported to have shown a positive association between serum concentrations and increased cholesterol, decreased bilirubin, low birth weight, immunological effects and cancer.

Based on these requirements set in place by the U.S. EPA, NSF created P473 to prescribe specific science-based test methods to evaluate drinking water treatment devices on their ability to reduce PFOA and PFOS in drinking water.


NSF P477: Drinking Water Treatment Units – Microcystin

NSF P477 includes requirements for verifying that point-of-use (POU) water filters can effectively reduce microcystins (toxins produced by blue-green algae) in drinking water. These requirements include precisely testing these filters throughout and beyond the manufacturer’s recommended treatment capacity with actual microcystins at levels representing some of the highest seen in drinking water, for reduction down to the 0.3 ppb (parts per billion) level recommended by the U.S. EPA for children under 6 years of age.

Water Purifiers

NSF P231: Microbiological Water Purifiers

NSF P231 establishes minimum requirements for health and sanitation characteristics of microbiological water purifiers. The requirements are based on the recommendations of the U.S. Environmental Protection Agency's Task Force Report, Guide Standard and Protocol for Testing Microbiological Water Purifiers (1987) (Annex B).

Military Operations

NSF P248: Military Operations Microbiological Water Purifiers

NSF P248 evaluates individual small water purifiers (SWPs) to determine their effectiveness in providing microbiological purification to water from any fresh water source. SWPs tested using this protocol are intended for individual or squad-size use for emergency or short-term planned missions. This protocol does not test or verify claims of chemical contaminant removal efficiencies.

Iodine Reduction

NSF/JWPA P72: Iodine Radioisotope Reduction

NSF/JWPA P72 was developed by NSF International and the Japan Water Purifier Association (JWPA) to effectively evaluate point-of-use drinking water treatment units to ensure that they reduce all common forms of iodine in drinking water.