ASSE 1085-2018 covers water heaters with precise setpoint controls under varying flow conditions. ASSE 1085 is for water heaters supplying tepid water to emergency equipment, including eyewash, eye/face wash, emergency showers, and combination units. These water heaters heat the cold water supply to an acceptable tepid temperature within the intended range listed in ISEA Z358.1.

The water heaters shall consist of a cold water inlet connection, a means of heating the water and controlling the discharge temperature, and an outlet connection to supply tepid water to the emergency equipment. The water heater shall also have a means to limit the maximum outlet temperature under normal operating conditions. Provisions shall be made so that the temperature setting of the water heater cannot be inadvertently adjusted.