UL 2581A:2014

1 Scope

1.1 These requirements cover expansion chambers used in water based fire protection systems.

1.2 The expansion chambers covered by these requirements are intended to absorb a volume of water or antifreeze solution caused by the effects of thermal expansion of the water or antifreeze solution in a portion of a fire protection system equipped with a backflow prevention device and not equipped with a pressure relief device as described in the Standard for Installation of Sprinkler Systems, NFPA 13. They are intended to be sized to accommodate the anticipated volume of water or solution and pressurized in accordance with the manufacturer's Installation and Design instructions.