11.4.2.2 — Increase in Occupant Load

(1) The performance level of an existing building is reduced where the existing building is extended or subject to material alteration or repair and a sewage system serving the existing building is adversely affected by the extension, alteration or repair of the existing building. (2) Except as provided in Sentence (3), the performance level of an existing building is reduced where proposed construction will increase the occupant load of an existing building, and the new occupant load will result in the total daily design sanitary sewage flow of the building, calculated in accordance with Article 8.2.1.3., exceeding the capacity of any component of a sewage system serving the building. (3) The performance level of an existing dwelling unit is reduced where proposed construction that, (a) increases the number of bedrooms in the dwelling unit, (b) exceeds 15% of the finished area of the dwelling unit, or (c) adds new plumbing fixtures to the dwelling unit, will result in the total daily design sanitary sewage flow of the dwelling unit, calculated in accordance with Article 8.2.1.3., exceeding the capacity of any component of a sewage system serving the dwelling unit. (4) The performance level of an existing building is reduced where proposed construction will result in the change of a major occupancy of all or part of the existing building to another major occupancy and, (a) the total daily design sanitary sewage flow of the proposed major occupancy, calculated in accordance with Article 8.2.1.3., exceeds the capacity of any component of a sewage system serving the building, or (b) the type or amount of sanitary sewage which will, under the proposed major occupancy, be discharged to a sewage system serving the building, is prohibited by Article 8.1.3.1.

(1) Reserved (2) Except as permitted by Sentences (3) to (5) and Sentence 3.2.4.2. (4), a fire alarm system shall be installed in a building that contains, (a) a contained use area, (b) an impeded egress zone, (c) more than 3 storeys, including storeys below the first storey, (d) a total occupant load more than 300, other than in open air seating areas, (e) an occupant load more than 150 above or below the first storey, other than in open air seating areas, (f) a school, college or child care facility, with an occupant load more than 40, (g) a licensed beverage establishment or a restaurant, with an occupant load more than 150, (h) a low hazard industrial occupancy with an occupant load more than 75 above or below the first storey, (h.1)a medium hazard industrial occupancy with an occupant load more than 75 above or below the first storey, (i )a residential occupancy with sleeping accommodation for more than 10 persons, (j) a high hazard industrial occupancy with an occupant load more than 25, (k) an occupant load more than 300 below an open air seating area, (l) an interconnected floor space required to conform to Articles 3.2.8.3. to 3.2.8.11, (m) a care and treatment occupancy for more than 10 persons receiving care or treatment, or (n) a care occupancy for more than 10 persons receiving care. (3) If each dwelling unit has direct access to an exterior exit facility leading to ground level, a fire alarm system is not required in an apartment building, (a) in which not more than four dwelling units share a common means of egress, or (b) that is not more than 3 storeys in building height. (4) A fire alarm system is not required in a hotel 3 storeys or less in building height provided each suite has direct access to an exterior exit facility leading to ground level. (5) A fire alarm system is not required in a storage garage conforming to Article 3.2.2.83. provided there are no other occupancies in the building.

(1) Except as permitted by Sentence (3), the minimum aggregate required width of exits serving floor areas intended for assembly occupancies, residential occupancies, business and personal services occupancies, mercantile occupancies, and industrial occupancies shall be determined by multiplying the occupant load of the area served by, (a) 6.1 mm per person for ramps with a slope of not more than 1 in 8, doorways, corridors and passageways, (b) 8 mm per person for a stair consisting of steps whose rise is not more than 180 mm and whose run is not less than 280 mm, or (c) 9.2 mm per person for, (i) ramps with a slope of more than 1 in 8, or (ii) stairs, other than stairs conforming to Clause (b). (2) The minimum aggregate width of exits serving floor areas intended for a care, care and treatment or detention occupancy shall be determined by multiplying the occupant load of the area served by 18.4 mm per person. (3) The minimum aggregate width of means of egress serving a Group A, Division 4 occupancy shall be determined by multiplying the occupant load of the area served by, (a) 1.8 mm per person for, (i) aisles, (ii) stairs other than exit stairs, and (iii) ramps and passageways in vomitories and exits, and (b) 2.4 mm per person for exit stairs. (4) Except as required by Sentence (5), the required exit width need not be cumulative in an exit serving two or more floor areas located one above the other. (5) The required exit width for an exit stair in an assembly hall or theatre serving more than one balcony level shall conform to the appropriate requirements for stairs serving interconnected floor spaces in Article 3.2.8.4. (6) If more than one exit is required, every exit shall be considered as contributing not more than one-half of the required exit width. (7) The width of an exit shall be not less than, (a) 1 100 mm for corridors and passageways, (b) 1 100 mm for ramps not serving patients’ or residents’ sleeping rooms, (c) 1 100 mm for stairs, not serving patients’ or residents’ sleeping rooms, that serve more than two storeys above the lowest exit level or more than one storey below the lowest exit level, (d) 900 mm for stairs, not serving patients’ or residents’ sleeping rooms, that serve not more than two storeys above the lowest exit level or not more than one storey below the lowest exit level, (e) 1 650 mm for stairs and ramps serving patients’ or residents’ sleeping rooms, (f) 1 050 mm for doorways serving patients’ or residents’ sleeping rooms, and (g) 790 mm for doorways not serving patients’ or residents’ sleeping rooms.