This Standard contains minimum requirements for onsite residential and commercial water treatment systems. Systems may include the following.

• Graywater treatment systems having a rated treatment capacity up to 5,678 L/day (1,500 gal/day). This applies to onsite residential and commercial treatment systems that treat graywater, those that treat laundry water from residential laundry facilities, and those that treat bathing water. See 8.1 for performance testing and evaluation.
• Commercial treatment systems — this applies to onsite commercial treatment systems that treat combined commercial facility wastewater and commercial facility laundry water of any capacity, and those treatment systems that treat graywater from commercial facilities with capacities exceeding 5,678 L/day (1,500 gal/day). These systems shall be performance tested and evaluated at the location of the reuse system installation, using the wastewater generated onsite from the facility serving the treatment system. See 8.3 for performance testing and evaluation. The key elements of a field evaluatin of a commercial treatment system are described in Annex A.

Management methods and end uses appropriate for the treated efflent discharged from onsite residential and commercial treatment systems meeting Class R (single family residential) or Class C (multi-family and commercial facilitiesds) requirements of this Standard include indoor restricted urban water use, such as toilet and urinal flushing, and outdoor unrestricted urban water use, such as surface irrigation. Effluent quality criteria consistent with these uses are described in 8.6, Criteria.

This Standard is intended to address public health and environmental issues. Actual performance for any site or system may vary, depending on variations in raw water supply (such as alkalinity and hardness), wastewater constituents, and patterns of use. The end use of the effluent is the responsibility of the owner, design professionals, and regulatory officials.

System components covered under other NSF or NSF/ANSI standards or criteria shall also comply with the requirements therein. This Standard shall in no way restrict new system designs, provided such designs meet the minimum specifications described herein.