On 04/07/07, ArchLinuxUser dick_turpin <dick_turpin(a)archlinux.us&gt; wrote: I don't know much about this, and I was basing my argument on things I've read that indicated that the canisters weren't likely to explode. Looking a bit further, this [1] would seem to suggest that the canisters *could* have exploded, if they'd done things like wound down a window to give the fire some air. That also fits in with your argument about arsonists - there's more air in a room than in a car, especially if the arsonist leaves a window open. Interestingly, though, the expert quoted also says "Even if those tanks exploded, they don't burst apart into thousands of pieces of shrapnel. They tend to break apart at the seam." I wouldn't put it past people making training films to exaggerate the effects of something in order to make a point. I've seen training films that showed how things *could* go, but failed to point out that it'd only go that way if a long series of unlikely events all went in just the right way. If there's not much explosion, and the main effect is fire, doesn't that affirm my belief that it'd be unlikely to damage the planes/whatever beyond the walls? I suspect you may be right - I don't know, but it seems reasonable to assume that they're primarily geared up for runway accidents. I vaguely remember the various terrorist groups of the 1970's, and I've read a fair bit about them. I can't help feeling that the threat then was at least as great as it is now, but people seemed a lot less concerned. What really bothers me is that people seem to be so scared of *everything* these days. Unlikely risks seem to be blown out of proportion, while likely risks are ignored. I'm sure it's always happened, but it seems more extreme these days. Russ [1] http://www.abcnews.go.com/International/story?id=3339093&page=1