Canadian Consulting Engineer

Sprinklers and Condominiums

A Private Member's Bill has passed two readings in the Ontario legislature proposing that sprinklers should be required in all new single-family homes. Bill 141 was introduced by Brampton MP Linda Jef...

May 1, 2005  By Bronwen Parsons

A Private Member’s Bill has passed two readings in the Ontario legislature proposing that sprinklers should be required in all new single-family homes. Bill 141 was introduced by Brampton MP Linda Jeffrey and supported by firefighters and others.

Yet, oddly, the same province allows condominiums to be built to any soaring height without requiring sprinklers to be installed, and so far no politician is proposing to change that situation. In contrast to Ontario, the National Building Code of Canada, which applies in much of the rest of the country, does require high-rise residential buildings — say a typical 10-storey condominium tower — to be sprinklered.

Ontario chose to deviate from the national norm in 1997. It was partly an economic decision, made at a time when the construction industry was in a terrible slump. Keeping building costs down was evidently considered more important than adding the best fire technology to suites with a panoramic view. Yet many high-rise apartment and condominium buildings are occupied by seniors who have limited mobility to get down many flights of stairs in an emergency. The argument against sprinklers in Ontario in 1995 was that the compartmentalization of residential structures afforded enough fire separation and protection.

Guylne Proulx of the National Research Council of Canada is a recognized expert in the evacuation of tall buildings in Canada and the U.S. She says the prime concern about fire protection in condominiums is the same as in any residential building — sleeping people might not hear an alarm or may not smell smoke immediately, so they can be slow to evacuate.

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She explains that the 9/11 commission that investigated the New York World Trade Center disaster has made several recommendations for protecting tall buildings. For example, the commission has recommended that all existing and new buildings have sprinklers. They also recommend that photoluminescent paint be used in stairwells to identify exit paths and that emergency lighting with battery packs is used in those locations.

The 9/11 recommendations are for office, not residential buildings. “The difficulty,” Proulx notes, “is to transfer the cost of these kinds of measures to condominium owners and renters.” Sprinkler systems add at least 4 inches to the floor height of each unit, so they add to the cost of a building in all its material aspects — an additional $8 million for a 50-storey building according to one estimate.

Ms. Proulx is working closely with researchers of the U.S. National Institute of Standards and Technology who are considering recommending that every tall building should have safe elevators for evacuating people. Safe elevators would be similar to existing dedicated firefighter elevators, with concrete shaft walls and smoke extraction equipment. Special sensors would ensure the elevators don’t serve floors where there is smoke. Safe refuge areas would have to be provided at boarding levels and in the lobbies where people disembark. Proulx believes that the difficult question would be how to manage people. For example, in an emergency when people are in a panic, who decides who should be first allowed to board the elevator?

The public address system is another critical component of fire safety. “When I talk to survivors of fires,” says Proulx, who helped investigate the 9/11 disaster, “always, the big critique people have is that no-one told them what to do, where to go, or what was going on.”

The instructions to occupants have to be precise, Proulx says. She also stresses that making sure tenants are prepared and know what to do if there is a fire is the most critical step. Unless the fire is in your own apartment, she says, it is usually better to stay put and seal cracks and openings to prevent smoke from seeping in, rather than to venture out and risk entering a smoke-filled stairwell.

Fire Alarms

Electrical engineers should also be aware that their design of fire alarm systems for high-rise residential buildings, hotels, condominiums, etc. is affected by changes in the forthcoming 2005 edition of the National Building Code of Canada. The change affects signal circuits serving fire alarm audibility devices in residential buildings covered in Part 3 of the code.

Philip Rizcallah, P. Eng., technical advisor and coordinator of fire safety at the Canadian Codes Centre of the National Research Council of Canada, explains that the changes are being made to accommodate new technologies and reduce problems that could occur when residents tamper with alarms inside their units. Often people disable the alarms when they become tired of them going off during cooking or from cigarette smoke.

The new NBC Article 3.2.4.19 will continue to ensure that someone disconnecting their in-suite audible alarm will not impair the operation of other residents’ alarms served by the same circuit. The 2005 provisions will allow a choice between the use of Class A circuitry, or Class B circuitry that incorporates signal circuit isolators located outside the suites.

Rizcallah explains that the change also requires that a single electrical circuit cannot serve multiple levels of the same building. In addition, the audible alarms within the common corridors must be on separate circuitry to the alarms inside the dwelling units.

Another provision does allow the alarm to be physically silenced by the resident within the dwelling unit for a period of up to 10 minutes. After that time, the device reverts back to normal conditions. A new provision allows this feature to be automated under specific conditions. These silencing features don’t affect the alarms in the common corridors, nor will they have an impact on the alarms in adjacent units.

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