UL (Underwriters Laboratories)
Establishes the minimum requirements for electric water heater safety.
- UL174: Residential Electric Water Heaters⎯ 12kW and less
- UL1453: Commercial Electric Water Heaters⎯ Greater than 12kW
ANSI (American National Standards Institute)
Establishes the safety and construction standards for gas products.
- Z21.10.1: Residential Gas Water Heaters⎯ 75,000 BTU/hr. and less
- Z21.10.3: Commercial Gas Water Heaters⎯ Greater than 75,000 BTU/hr.
DOE (Department of Energy)
EPCA was enacted in 1975, which then led to the first NAECA (National Appliance Energy Conservation Act) in 1987. The Energy Policy Act of 1992 (EPACT92) covers commercial products.
ASHRAE (American Society of Heating Refrigeration and Air Conditioning Engineers)
Sets the minimum requirements for overall efficiency of buildings with the exception of low-rise buildings.
- ASHRAE 90.1B: Pertains to minimum efficiency of all water heaters installed in buildings.