(a) If a required Path of Travel to an exit is within an atrium, a suitable alternative power supply must be provided to operate required safety systems, including sprinkler systems and fire hydrant pumps, air handling systems, alarms, warning and communication systems and emergency lighting circuits.

(b) The alternative power supply must—

(i) be connected automatically if the normal power supply fails; and

(ii) if located within the building, be separated from the remainder of the building by an enclosure with an FRL of at least 120/120/120; and

(iii) be connected to the safety systems by means of cabling complying with C2.13(c)(iii) and (iv).

(c) The requirements of (a) are satisfied by—

(i) a single medium voltage supply taken from an electricity substation situated within, or adjacent to, the building concerned where the power supply to the substation consists of two or more high voltage cables each taking electricity from separate transformers; or

(ii) two or more medium voltage supplies each taking electricity from separate electricity substations situated—

(a) outside the building concerned; and

(b) at a suitable distance from each other; or

(iii) a single medium voltage supply taken from an electricity substation together with an electricity generating plant capable of—

(a) generating a medium voltage supply; and

(b) starting and taking the required electrical load within a period of not more than 30 seconds from the time of normal supply failure.

Where you can go to see what is fully required to comply?

Maintenance Standard

• NFPA110

Minimum Standards of Performance

• BCA Specification G3.8 point 6 Stand by power system

• AS3000

Inspection Intervals

All routine inspected and tested shall be in accordance with AS1851-2012