(1) A rooftop enclosure provided for elevator machinery, a stairway or a service room used for no purpose other than for service to the building, shall not be considered as a storey in calculating the building height. (2) Space under tiers of seats in a building of the arena type shall not be considered as adding to the building height provided the space is used only for dressing rooms, concession stands and similar purposes incidental to the major occupancy of the building. (3) Except as required by Sentence (5), the space above a mezzanine need not be considered as a storey in calculating building height provided,
(a) the aggregate area of mezzanines that are not superimposed does not exceed 40% of the open area of the room in which they are located, and
(b) except as permitted in Sentence (8) and Sentence 3.3.2.11. (3) the space above the mezzanine is used as an open area without partitions or subdividing walls higher than 1 070 mm above the mezzanine floor. (4) Except as required by Sentence (5), the space above a mezzanine need not be considered as a storey in calculating the building height provided,
(a) the aggregate area of mezzanines that are not superimposed and do not meet the conditions of Sentence (3) does not exceed 10% of the floor area in which they are located, and
(b) the area of mezzanine in a suite does not exceed 10% of the area of that suite. (5) Except as permitted by Sentences (6) and (7), each level of mezzanine that is partly or wholly superimposed above the first level of mezzanine shall be considered as a storey in calculating the building height. (6) Platforms intended solely for periodic inspection and elevated catwalks need not be considered as floor assemblies or mezzanines for the purpose of determining building height provided,
(a) they are not used for storage,
(b) they are constructed with noncombustible materials unless the building is permitted to be of combustible construction, and
(c) where they are intended to be occupied, they have an occupant load of not more than four persons. (7) Mezzanines, elevated walkways and platforms that are intended to be occupied in Group F, Division 2 or 3 major occupancies need not be considered as storeys in calculating building height provided,
(a) the building is of noncombustible construction, and
(b) the occupant load is not more than four persons. (8) The space above a mezzanine conforming to Sentence (3) is permitted to include an enclosed space whose area does not exceed 10% of the open area of the room in which the mezzanine is located, provided the enclosed space does not obstruct visual communication between the open space above the mezzanine and the room in which it is located. (9) A service space in which facilities are included to permit a person to enter and to undertake maintenance and other operations pertaining to building services from within the service space need not be considered a storey if it conforms to Articles 3.2.5.15. and 3.3.1.23. and Sentences 3.2.4.20. (12), 3.2.7.3. (2), 3.3.1.3. (7), 3.4.2.4. (3) and 3.4.4.4. (9).
(1) Except as provided by Sentences (9) and (10), every exit door shall have an exit sign placed over or adjacent to it if the exit serves,
(a) a building more than 2 storeys in building height,
(b) a building having an occupant load of more than 150, or
(c) a room or floor area that has a fire escape as part of a required means of egress. (2) Except as provided by Sentence (7), every exit sign shall,
(a) be visible on approach to the exit,
(b) consist of a green pictogram and white graphic symbol meeting the visibility specifications referred to in ISO 3864-1, “Graphical Symbols – Safety Colours and Safety Signs – Part 1: Design Principles for Safety Signs and Safety Markings”, and
(c) conform to ISO 7010, “Graphical Symbols - Safety Colours and Safety Signs - Registered Safety Signs” for the following symbols:
(i) E001 emergency exit left,
(ii) E002 emergency exit right,
(iii) E005 90-degree directional arrow, and
(iv) E006 45-degree directional arrow. (3) Internally illuminated exit signs shall,
(a) be continuously illuminated, and
(b) where illumination of the sign is powered by an electrical circuit, be constructed in conformance with CSA C22.2 No. 141, “Emergency Lighting Equipment”. (4) Externally illuminated exit signs shall be continuously illuminated by a light fixture supplied by an electrical circuit. (5) Photoluminescent and self-luminous exit signs shall,
(a) conform to CAN/ULC-S572, “Photoluminescent and Self-Luminous Signs and Path Marking Systems”,
(b) be labelled in accordance with the time duration for which they have been tested and listed,
(c) be so installed that upon failure of the regular power they will continue to be illuminated for the applicable time duration specified in Clause 3.2.7.4. (1)(b), and
(d) be continuously illuminated if reliant on an external energy source to energize the reflective coating of the sign. (6) If illumination of an exit sign is provided from an electrical circuit, that circuit shall,
(a) serve no equipment other than emergency lighting in the area where exit signs are installed, and
(b) be connected to an emergency power supply as described in Sentence 3.2.7.4. (1)
(7) Where no exit is visible from a public corridor, from a corridor used by the public in a Group A or B major occupancy or from principal routes serving an open floor area having an occupant load of more than 150, an exit sign conforming to Clauses (2)(b) and (c) with an arrow or other indicator pointing at the direction of egress shall be provided. (8) Except for egress doorways described in Sentence 3.3.2.3. (4), an exit sign conforming to Sentences (2) to (6) shall be placed over or adjacent to every egress doorway from rooms with an occupant load more than 60 in Group A, Division 1 occupancies, dance halls, licensed beverage establishments and other similar occupancies that, when occupied, have lighting levels below the level that would provide easy identification of the egress doorway. (9) Except for suite doors opening directly to the exterior, every exit serving a hotel shall have an exit sign placed over or adjacent to it. (10) An exit sign is not required within a suite containing a Group B, Division 3 occupancy if the following requirements are met:
(a) the suite contains sleeping accommodation for not more than 10 persons, and
(b) not more than 6 occupants require assistance in evacuation in case of an emergency.