NSF International has been approved to conduct tests and plant audits to criteria set for the Japanese Water Mark. Recognized by the Japanese Ministry of Health and Welfare, the Japanese Water Mark is a certification tool for water supply equipment, used to determine the conformity of products to specific Japanese standards. NSF is the only U.S. organization authorized to provide these services in support of obtaining the Japanese Water Mark for manufacturers of drinking water treatment units and plumbing products.

Through a partnership with the Japanese Gas Appliances Inspection Association (JIA), all NSF's audits and evaluations performed under the Japanese Industrial Standards JIS S 3200 series standards will be accepted by JIA without the need for further evaluation.