I have a question about a house fire scenario and I'm hoping there is someone here who could help me out a bit.
Question: In the event that a house burns to the ground (total loss), how long is it before the fire department leaves the scene and the debris is cool enough for someone to sift through? I'm sure there are environmental factors, so imagine summer in a humid area. The size of the house, basement, and construction will make more of a difference than the weather. Let's use a three bedroom, one-story ranch made in the mid-seventies, with a full basement.
Alarm is delayed until the building is fully involved, and by the time the first unit arrives on scene, an interior attack is no longer possible. The fire began in the basement. This would be at least a half hour and probably more than an hour from the beginning of the fire. (If I can get an interior attack going, I've never lost a structure into the basement. It can happen, but you've got to make some mistakes in fighting the fire.)
External attacks are launched, using 2.5 inch hose, with probably about four streams going. Main concern would be preventing spread, and secondary concern would be knocking down flames. Four streams of water is going to be about 2,000+ gallons a minute, which is pushing most water supplies. Assuming I've got enough water, I'd expect to have the flames knocked down in about an hour to two hours.
For the next two to four hours I'll be pouring water on the structure, trying to cool it down. I'd probably go down to about a 1,000+ gallons a minute, and two or three 1.75 inch hoses (2.5 inch hose takes a lot of work). I'm assuming by this point that the structure has settled into the basement, although some walls might still be standing. By the end of this period, we'd be reducing equipment and manpower. We'd also begin using poles to get at the ashes.
If there is something that we need to look for, if it can be done safely (fire fighter's definition, not a sane person's definition), we'd start looking at the end of this period. Substantial amounts of steam and some smoke would still be rising.
After this, for the next twelve hours or so I'd probably keep a truck on the scene, occasionally flowing water as hot spots appear. Search of the ashes could be done by fire fighters at this point.
Once I was sure there were no hot spots, I'd release the scene to the owner. I'd tell him to stay out of the basement, but figure he'll be down there before I get to the station.
Actually, I have another question. Would a locking fire safe(the small, portable kind with a handle) really survive a full-fledged blaze? Would it still open with a key or would the heat make alternative methods necessary? I'm imagining that intense enough heat would fuse the materials. Wrong or right? Safes are rated for both heat and endurance. You're looking at a safe in the 1700+ degree temperature range and a minimum of two hours. This would not be a small, portable one. Those things won't survive a fire like this without significant damage, and probably interior objects being destroyed.
But you need to understand fire is a funky thing. If a wall collapsed on the safe early on, and it was buried in wallboard, it's completely possible for it to survive. Of course, it's going to be a bitch to find the damn thing. I've seen newspaper survive major fires. It just depends upon how everything happens.
Any help appreciated. Thanks!
km
