What would happen if the CN Tower actually caught fire?

A week ago, folks in downtown Toronto looked up, and were surprised and concerned to see big plumes of smoke billowing from the observation deck of the city’s iconic CN Tower.

Multiple 911 calls went out from onlookers, afraid a major fire was engulfing a 553-meter-tall building that was the world’s tallest free-standing structure from the mid-70s until 2010.

False alarm. It turned out the smoke came from a pyrotechnic display tied in with a rehearsal for the opening ceremonies of the Pan-Am Games.

The crisis dissipated with the smoke, but it left behind a lingering question:

What would happen if the CN Tower ever caught fire for real?

For an answer, we called the fire department.

“The secret for that place is actually the use of the elevators,” said Andrew Kostiuk, a division commander with Toronto Fire Services.

“We’d have the elevators to get the fire-fighting forces up to the restaurant area, or wherever the fire might occur. Most likely it would be the restaurant, due to the cooking elements, although they do all their cooking below and actually raise it up by elevator.”

That seems counter-intuitive. In most buildings, Article One of the emergency evacuation procedures is to never use the elevators during a fire.

“The CN Tower’s elevators are outside the building, and on top of concrete,” Kostiuk explains.

“The chance of a fire being severe enough to affect them is extremely low.”

No one from the tower was available for an interview, but management sent over a bunch of material detailing emergency procedures.

So how do you protect visitors and staff in a building more than half a kilometer tall?

“The CN Tower routinely conducts tests and drills of all systems, including comprehensive evacuation drills twice each year,” tower management says.

“These efforts are to ensure all systems are functioning at their peak efficiency.”

Kostiuk says the tower’s official capacity is 2,700 – a number that people who have been there would likely find surprisingly high.

“That’s a lot of people,” he notes. “More than you would think in a place like that if you’re looking at it from the bottom.”

With only six elevators and a whopping 1,776 stairs from the ground to the SkyPod, it’s no wonder the tower places a huge importance on fire prevention.

“There is no open flame in the building used for cooking or ambience,” management says.

“There is significant water access at the top of the CN Tower. Two major reservoirs each contain 15,000 gallons of water. Additionally, the reservoirs auto-replenish as required.

“In addition to two reservoirs, the CN Tower has the ability to pump 600 gallons of water per minute to the top of the tower for the extensive sprinkler network. Generators located at the base of the CN Tower power the fire pumps. The pumps are routinely inspected and tested.”

From the fire department’s point of view, Kostiuk praises staff at the tower for their procedures and preparedness.

“The CN Tower is a well-run place,” he says.

“They’ve got mobile cameras that cover almost the whole place, all the time. So the beauty for us is, if we had a real fire, we’d put a district chief in the security operations centre, and we’d be able to see their whole operation by remote camera. That gives us a pretty good idea of where the fire is, and where people may be in need of assistance.”

What we have, then, is a building made almost entirely of fire-proof materials – concrete, glass and metal – with water constantly circulating and a surveillance system that monitors practically all of the tower, all the time.

“That would have all been part of the building design back then, the building department approval and the fire prevention approval,” Kostiuk concludes.

“We’ve been fortunate [in Toronto] that we have never had a serious commercial high-rise fire.”