6.5.2 Emergency Power System

An emergency generator provides an alternate source of power should utility power become unavailable to critical life-safety systems such as alarm systems, egress lighting fixtures, exit signs, emergency communications systems, smoke-control equipment, and fire pumps.

Emergency generators typically require large louvers to allow for ventilation of the generator while running. Care should be taken to locate the generator so that these louvers are not vulnerable to attack. A remote radiator system could be used to reduce the louver size.

Redundant emergency generator systems remotely located from each other enable the supply of emergency power from either of two locations. Consider locating emergency power-distribution feeders in hardened enclosures, or encased in concrete, and configured in redundant routing paths to enhance reliability. Emergency distribution panels and automatic transfer switches should be located in rooms separate from the normal power system (hardened rooms, where possible).

Emergency lighting fixtures and exit signs along the egress path could be provided with integral battery packs, which locates the power source directly at the load, to provide lighting instantly in the event of a utility power outage.