NSF has developed over 80 currently active voluntary American National Standards for public health, safety, environment and sustainability assessment.

Accredited by the American National Standards Institute (ANSI), NSF has developed over 80 currently active voluntary American National Standards under the scope of public health, safety, environment and sustainability assessment.

NSF/ANSI standards are developed through a public process that ensures balanced input from industry representatives, public health/regulatory officials and users/consumer representatives.

There are several representative standards that cover the decontamination performance of water purifier products and water purifiers. Manufacturers choose which contaminants the water purifier removes, and NSF International tests and certifies the water-purifying performance claimed by the manufacturer. It is important to check both the standard name (e.g., NSF/ANSI 53 or NSF/ANSI 58) and the specific contaminant (e.g., lead) removal performance on the product packaging.