The start of any fire must be detected as quickly as possible, and certainly before it can make the means of escape unusable. In some circumstances, particularly where occupants are located away from the origin of the fire and there is a reasonable possibility that it could spread, this means that the fire must be detected and occupants alerted within the first minute of ignition. This will allow building occupants enough time to escape. As clearly described in the fire safety plan for buildings, the use of elevators is to be avoided in the event of a fire. For many occupants, this directive may seem to be at odds with the need to exit a building as quickly as possible, but there are significant reasons why occupants should not use an elevator during a fire evacuation. An elevator shaft may act like a chimney during a fire, concentrating smoke in the shaft and resulting in riders suffering from smoke inhalation or even burns. The approved fire safety plan will detail all the safety interlocks of the building elevators, such as automatic recall to a specific floor when the fire alarm system is activated. In addition, the fire safety plan outlines the building operator’s responsibly to follow the maintenance requirements of the fire and life protection equipment within the building. This not only applies to the elevators and smoke controls, but includes the fire alarm and sprinkler systems, emergency lighting and exit fixtures, hose stations and fire extinguishers.
Regardless of the location, once occupants become aware of a fire they must be able to proceed safely along easily-recognized escape routes to a designated location. To achieve this aim, it is mandatory to protect the route with fire-resisting construction. This protection is mainly defined as the use of fire-rated barriers, fire doors and other features to provide protected egress. The concept behind protected egress is to create an envelope or continuous path of relative safety for the evacuation of occupants. The entire exit needs to be free of smoke, heat, combustion gases and other by-products of a fire so as to ensure safe and efficient evacuation. Fire codes require corridors and stairways in most occupancies to be of fire-rated construction materials and design. The doors between adjoining rooms must meet a specific fire-resistance rating and be equipped with automatic door closers. Fire-rated barriers include corridor walls, floors and ceiling. No penetrations or openings are allowed between the corridor space and adjoining rooms or other floors, except for the normally-closed doors between the corridors and rooms. The opening or leaving ajar of even just one door could allow smoke and heat to enter the exit way and threaten evacuees. This could very quickly render the exit protection useless, making it impossible for people to reach a stairway and exit to safety. Stairways are an integral part of the protected egress and, as they provide a connection between floors, they must be constructed to have a much higher fire-resistance rating than corridors. Despite the provisions of protection specified in the codes, walls with openings inherently have less fire resistance than unpierced walls. Fire doors are designed to protect an opening under normal conditions of use, which means ensuring a clear space on both sides of the opening. When the opening is not in regular use and combustible material is piled against a door, window or shutter, the same level of designed protection cannot be expected. Combustible material should be kept well away from openings.
This article was contributed by Firepoint Inc, serving the GTA since 1997, developing fire department approved fire safety plans for newly constructed and existing buildings. Although every effort is made to ensure the accuracy, currency and completeness of the information, the bulletin publishers and authors do not guarantee, warrant, represent or undertake that the information provided is correct, accurate or current and shall not be liable for any loss, claim, or demand arising directly or indirectly from any use or reliance upon the bulletin information. Bulletin reproduction in whole or in part is prohibited without the written consent of Firepoint Inc. Copyright 2021 – All Rights Reserved. See www.firepoint.ca or call 905-874-9400.