Rule 46-400 Exit Signs (see Appendices B and G)
(1) Where exit signs are connected to an electrical circuit, that circuit shall be used for no other purpose.
(2) Notwithstanding Subrule (1), exit signs shall be permitted to be connected to a circuit supplying emergency lighting in the area where these exit signs are installed.
(3) Exit signs in Subrules (1) and (2) shall be illuminated by an emergency power supply where emergency lighting is required by the National Building Code of Canada.
Rationale for Rule 46-400. This Rule establishes the requirements pertaining to the power supply for exit signs.
Intent for Rule 46-400. Building codes provide the requirements for the location of illuminated exit signs.
If an exit sign is required by the building code, we intend that the power supply for the exit sign be provided from a branch circuit that supplies only other exit signs or a circuit supplying emergency lighting. We also intend that, in the area where exit signs are installed, and where emergency lighting is required by the National Building Code of Canada or local building codes, exit signs be illuminated by an emergency power supply. The exit signs shall be permitted to be connected to the emergency lighting in the area. This requirement ensures that the exit sign will be lit whenever the emergency lighting is energized.
The note in Appendix B cautions that the circuit supplying both emergency lighting and exit signs should not be controlled by a switch, time clock, or other means.
ONTARIO BULLETIN #46-1-4
Supersedes Bulletin 46-1-3 (November 1996)
Emergency Lighting and Exit Signs
Rules 46-304 and 46-400 (page 196)
The Ontario Building Code prescribes the supply conditions for electric emergency lighting and exit signs in Articles 3.4.5, 188.8.131.52, 9.9.10 and 9.9.11. The wiring requirements for such equipment are in Section 46 of the Ontario Electrical Safety Code.
Section 46 applies to buildings where emergency lighting and exit signs are required by the Ontario Building Code.
Rule 46-304 (4) requires:
“Unit equipment shall be installed in such a manner that it will be automatically actuated upon failure of the power supply to the normal lighting in the area covered by that unit equipment.”
This is not always practical, in areas such as large retail areas, a gymnasium in a school or a manufacturing area in a factory. In these areas most of the circuits could fail and the light levels would be such that persons within could safely exit the building.
For buildings or large areas separated by fire walls, within the scope of Part 3 of the Ontario Building Code, such as the retail area in a store , gymnasium in a school or a manufacturing area in a factory, the phrase "the failure of the power supply to the normal lighting in the area covered by unit equipment" is interpreted to mean failure of the regular power supply to the building. An acceptable method to satisfy the requirement is to supply the unit equipment from a branch circuit in the panel supplying the lighting.
There are separate requirements for the activation of emergency lighting and exit signs in buildings within the scope of Part 9 of the Ontario Building Code.
Part 9: Buildings
Unit equipment installed in buildings within the scope of part 9 of the Ontario Building Code , shall be installed in such a manner that it will be automatically actuated upon failure of the power supply to the normal lighting in the area covered by that unit equipment.
Exit Signs Installed where not required by the Ontario Building Code
There are no special requirements in the Ontario Electrical Safety Code for exit signs installed voluntarily.
To eliminate controversy in the field and to assure a degree of uniformity in wiring arrangements, the following practices are acceptable for wiring exit signs not required by the Ontario Building Code:
(1) Conductors supplying exit signs shall be installed in accordance with Section 12.
(2) Appliances, lamps, or devices other than those required for exit signs shall not be supplied by the branch circuit supplying the exit signs.
(3) Branch circuit overcurrent and control devices shall be operable by or accessible to authorized persons only.
To assure that exit lights are not inadvertently switched off in an emergency, it is desirable that branch circuit connections be made as close to the service entrance as possible.
Responsibility for interpreting the Ontario Building Code rests with the municipal building departments, which should be consulted on questions concerning the requirements of the building code concerning the necessity for emergency lighting and exit signs in any particular building.
Electrical Safety Authority