Whenever we had fire drills at school, we had people designated to close the windows, presumably to prevent drafts from fanning the flames, or letting smoke in from outside.

But I've also seen fire-fighters punch holes in roofs and walls to vent smoke. Smoke-venting can improve both visibility and survivability.

The newest innovation in building automation should be windows that have the ability to open and close themselves on signals from fire alarm systems and smoke detectors, (and I suppose any novel people-locating systems that the automation is connected to). Whether the correct behavior is being opened or closed, the windows should be programmed to do the right thing automatically.

Personally, I would program my window to shut when a passing cigarette smoker is detected. It's ridiculous how often people walk by and waft noxious fumes into my room.
-- beland, Sep 27 2003

The one thing you *do not* want in a fire is automatic windows. All too many automatic elevators get stuck on the wrong floors in fires due to their heat-activated buttons. Self-closing windows could easily injure someone trying to escape from a burning building. And you certainly don't want self-opening windows messing with the fire brigade's carefully orchestrated schemes to vent the smoke.
-- DrCurry, Sep 27 2003


Well, I certainly wouldn't want the windows designed such that they close on somebody and injure them, whether or not there's a fire. They should notice when there's an obstruction, and give up, like an elevator door or subway car door.

If self-opening windows are going to mess with smoke-venting schemes, then you program the windows to shut themselves and stay that way unless someone comes along and opens them manually. And once the alarm has gone off and they close, they shouldn't change state and introduce unpredictability into fire-fighting attempts.

It seems to me that if the classroom windows need to be shut when the fire alarm goes off, it's much better to program the windows to close themselves, than it is to program all of the children in the last row to close all the windows. The children should use those seconds to evacuate that much sooner.

The dorm-like house I used to live in had self-closing internal doors that activated when the fire alarm went off - just a simple magnet and a spring. They were a very good thing, and it would be even better if the windows had been just as smart.
-- beland, Sep 28 2003


I haven't been in school for a while, but none of the office buildings I've seen lately have windows you can open... probably the energy conservation concept at work. BTW, I have NEVER heard of a fire-fighter punching a hole in a wall to improve survivability... this provides a fresh source of oxygen to fuel the fire, which is why the doors close automatically in the event of fire and why children were told to close the windows, and why they say touch doorknobs first during a fire and if it's hot, don't open it... doing so would introduce fresh oxygen which could fireball. Firefighters carry their own oxygen tanks, so "survivability" shouldn't be a driving issue there.
-- musicator, Sep 28 2003


I've actually seen them punch holes in roofs and *external* walls higher up to vent the smoke. I've also seen them open the front door and put a gigantic fan in front to drive the smoke out of other openings. It may be a good idea to cut off the air supply while waiting for the fire department to get there, to contain the fire as much as possible, and to prevent smoke from spreading to distant parts of the building. (So close-only automatic windows may very much be the right thing.) But when the fire department gets there and is ready to go in, they need to clear the smoke so that they can a.) find any unconscious people lying around, b.) find the fire, and c.) find their way out.
-- beland, Sep 28 2003


In New York, highrises must have a dedicated fan that can only be turned on manually. There are remote controlled hatches on every floor that lets you isolate a floor so when there is too much smoke on floor 12, you isolate the floor with the hatches and have the fan suck all the air out of the floor in one minute. Don't bother with windows. What if the classroom doesn't have windows? Must all classrooms be where they can get windows?
-- felipefas, Apr 16 2004


Structure fires spread when hot gasses move from areas that are on fire to those that aren't yet. A major goal in fighting structure fires is thus to keep hot gasses away from the parts of the structure that aren't on fire.

To use a crude analogy, a candle will burn with no draft, and will burn slightly better with a small draft, above a certain point stronger drafts will impede combustion until a point is reached where combustion is interrupted entirely. Most structure fires are well-enough aspirated naturally that adding additional ventilation will actually impede combustion provided that the additional ventilation drives the hot gasses away from the combustible materials.
-- supercat, Apr 17 2004



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