The Ontario Building Code | Emergency Power for Fire Alarm Systems
3.2.7.8. Emergency Power for Fire Alarm Systems
(1) Fire alarm systems, including those incorporating a voice communication system, shall be provided with an emergency power supply conforming to Sentences (2) to (4).
(2) The emergency power supply required by Sentence (1) shall be supplied from,
(a) a generator,
(b) batteries, or
(c) a combination of the items described in Clauses (a) and (b).
(3) The emergency power supply required by Sentence (1) shall be capable of providing,
(a) supervisory power for not less than 24 h, and
(b) immediately following, emergency power under full load for not less than,
(i) 2 h for a building within the scope of Subsection 3.2.6.,
(ii) 1 h for a building classified as Group B major occupancy that is not within the scope of Subsection 3.2.6.,
Note: On July 1, 2017, Clause 3.2.7.8.(3)(b) of Division B of the Regulation is amended by adding the following Subclause: (See: O. Reg. 139/17, s. 34)
(ii.1) 1 h for a building that contains a Group C major occupancy retirement home and that is not within the scope of Subsection 3.2.6.,
(iii) 1 h for a building within the scope of Article 3.2.2.43A. or 3.2.2.50A.,
(iv) 5 min for a building not required to be equipped with an annunciator, and
(v) 30 min for any other building.
(4) The emergency power supply required by Sentence (1) shall be designed so that, in the event of a failure of the normal power source, there is an immediate automatic transfer to emergency power with no loss of information.
In Plain Language
This clause sets requirements for periodic testing of emergency power systems, ensuring generators and transfer switches are verified to work correctly rather than being assumed reliable without regular checks.
This is a plain-language summary of the 2012/2017 Ontario Building Code text above, for general understanding only and not a substitute for the Code. Always confirm current requirements against the 2024 edition (O.Reg. 163/24) or a qualified professional before construction.