New NSF/ANSI/CAN 61 Provision Solves Compliance Challenge for On-Site Chemical Generators

For years, certification of on-site chemical-generating equipment, such as electrolytic chlorinators, has been covered under the scope of NSF/ANSI/CAN 61: Drinking Water System Components (NSF 61).

Certification of these products under NSF 61 entails the evaluation of chemical leaching from the equipment’s constituent materials into the produced drinking water treatment chemical. Thus, while certification under NSF 61 ensures the chemical generator is not leaching harmful contaminants into the drinking water system, it does not evaluate the substances produced by the equipment.

Chemicals produced by chemical generators could previously be evaluated to NSF/ANSI/CAN 60: Drinking Water Treatment Chemicals – Health Effects (NSF 60), but only after the generator was installed and operating in a specific water treatment facility.

Historically, this has posed a problem for water utilities that require all drinking water treatment chemicals to comply with NSF 60, placing the burden of this evaluation on states or local water utilities for each installation.

The Drinking Water Additives Joint Committee, which oversees NSF 61, recognized the need for manufacturers to claim compliance with NSF 60 for the chemicals generated by their NSF 61-certified equipment before sale and installation. Therefore, a new provision within NSF 61’s 2025 edition was added to meet this need.

The standard now allows chemicals produced by NSF 61-certified chemical generators to be evaluated to the requirements of NSF 60 at the discretion of the manufacturer.

Existing criteria

• NSF 61: Health effects of chemical generator devices.
• NSF 60: Health effects of on-site generated chemicals.

New criteria

• NSF 61: Health effects of chemical generator devices + on-site generated chemicals.

Only chemicals meeting the scope of NSF 60 are eligible and must meet all the requirements specified in NSF 60. To give you an idea, some of those requirements include:

• Evaluation at a maximum use level (MUL) compliant with standard requirements, including evaluation of alternate feedstock chemicals.
• Preparation of analytical sample according to the requirements of NSF 60.
• Analysis according to the test batteries specified in NSF 60, including any formulation-dependent analytes.
• Sampling of the dosed chemical from the chemical generator operating within the equipment manual specifications.

Additionally, the chemical generator equipment, installation manual and operating manual must bear a label indicating that the product chemical complies with NSF 60. The label must also note the MUL, feedstock chemicals and strengths, and the requirement to operate according to manual specifications.

The label also notes that monitoring source water characteristics and maintaining the quality control of the produced chemical are the responsibility of the equipment operator.

If you’d like to see this new provision for NSF 60 evaluation of chemicals produced by NSF 61-certified chemical generators, it is detailed in Section 8 of the 2025 version of NSF/ANSI/CAN 61.

NSF’s public listings for on-site chemical generators will include footnotes to indicate when the product chemicals comply with the new NSF 60 evaluation requirements.

With this new evaluation option, manufacturers of NSF 61 certified on-site chemical generation equipment may now also claim compliance with NSF 60 for the chemicals produced by their equipment, even when the equipment is not installed at a specific water utility.