Codes & Standards

Background Information on Plumbing Standards

Plumbing Standards are a key avenue to advancing water efficiency in plumbing fixtures. The National Energy Policy Act sets maximum flow standards for showerheads, faucets, urinals, and toilets, but how those standards are manifested in fixtures is a function of standard setting. Since 1994, water utilities are increasingly becoming more aware of and involved in this standard setting process, but overall the water efficiency community needs a better understanding of how and why these standards function if they are to have an impact on improving water efficiency in the affected fixtures.

The standards are developed and administered in a complex process. The American Society of Mechanical Engineers (ASME) and the International Association of Plumbing and Mechanical Officials (IAPMO) are both accredited by the American National Standards Institute (ANSI) to develop U.S. standards for plumbing fixtures and fittings. Within these organizations, the ASME A112 and IAPMO Z124 committees are developing and maintaining standards related to toilets, urinals, showerheads, faucets, pre-rinse spray valves, and other fixtures and fittings used in indoor plumbing systems.

Standards committees and project teams are comprised of a variety of stakeholder interests, and are required by ANSI to maintain a “balance” of those interests. As such, these groups include representatives of manufacturers, laboratories, government, private sector consultants, and others. The Alliance is now one of those interests represented, and will work aggressively to help the evolution toward more efficient products. Examples include reducing the urinal flush volume maximum from 1.0-gallons to 0.5-gallons (3.78 L to 18.92 L), modifying the standard to enable the introduction of 1.0-liter flushing urinals, and refining the standard for pre-rinse spray valves. If implemented, each of these actions could significantly affect indoor water consumption throughout the country.

There are numerous committees that develop plumbing fixture standards, such as the following: