The Ontario Building Code | Emergency Power for Lighting

3.2.7.4. Emergency Power for lighting="http://thehandyforce.com/electrical/" title ="East York Electrician">lighting

(1) An emergency power supply shall be,

(a) provided to maintain the emergency lighting="http://thehandyforce.com/electrical/" title ="East York Electrician">lighting required by this Subsection from a power source such as batteries or generators that will continue to supply power in the event that the regular power supply to the building is interrupted, and

(b) so designed and installed that upon failure of the regular power it will assume the electrical load automatically for a period of,

(i) 2 h for a building within the scope of Subsection 3.2.6.,

(ii) 1 h for a building of Group B major occupancyclassification that is not within the scope of Subsection 3.2.6.,

Note: On July 1, 2017, Clause 3.2.7.4.(1)(b) of Division B of the Regulation is amended by adding the following Subclause: (See: O. Reg. 139/17, s. 33)

(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., and

(iv) 30 min for any other building.

(2) If self-contained emergency lighting units are used, they shall conform to CSA C22.2 No. 141, "Emergency Lighting Equipment".

In Plain Language

This clause sets requirements for how long an emergency power source must be able to run and which specific loads (life-safety systems versus general building loads) it must be sized to support.

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.