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Saturday, June 23, 2012

In-unit fire alarms should shut down appliances

Listen to a few fire dispatches and you start to get ideas about safety equipment. One of them seems obvious after you hear a bunch of the same call over and over again.

It basically goes like this: someone in an apartment complex or in a group of condos hears a smoke alarm going off inside a unit. There's no answer at the door, and there's smoke coming out. They call 911 and that leads to a full structure response from the fire department.

Now you have four engines, a truck, a battalion chief and maybe more, plus a couple of police units to assist with traffic or possibly deal with other related problems in the area. This represents a nontrivial percentage of the resources in the city.

The first fire unit on scene goes up and ultimately smashes down the door. They get inside and discover... it's a pot on the stove. Someone left it on, and it boiled off the water, and eventually caught on fire (or similar). Eventually, the smoke and/or flames tripped the alarm.

Here's what I don't understand: if the unit has an alarm, why doesn't it have some kind of interlock with the stove? If it's electric, chop the power. If it's gas, close the valve. Sure, that won't put out the fire, but it definitely will keep it from getting worse.

Even if the interlock fails to function, it results in what we have now, which is a fire which keeps being fed by the stove until someone stops it.

If you've spent any amount of time in a modern building, you've probably experienced fire alarm interlocks, possibly without realizing it. If you've been there when the alarm goes off and heard *boom* *slam* *bonk* all over the place a second or two later, that was it. The electro-magnetic door-holders all shut off when an alarm is activated, and all of those doors slam shut on their own. The building's elevators probably also all return to the ground floor.

Apartment complex owners have a lot to lose from runaway unattended kitchen fires. They also maintain the fire alarm and major appliances. This just seems obvious to me. Hook them up!