Ever see the old depictions of a blacksmith at work, hammering iron into shape with tongs and an anvil?
The Smith heats the iron to make it soft, so it can be molded and shaped. I’ve done it myself. If the steel is “only” orange-hot, far lower in temperature than it’s “melting” point as several commentators have used, I can grab a one-inch square steel bar with plain shop pliers and bend it almost double by hand.
The planes carried tons of jet fuel, which burns somewhat slower than gasoline, jet fuel which puddled on floors and just sat there and burned. Add the furniture, wiring, walls, carpeting and other flammables, and I’m quite sure that many sections of steel saw temperatures well in excess of 1,500 degrees, for upwards of an hour.
Add to that the fact that, according to one site I read today, each floor weighed some six million pounds, and there were what, another thirty floors above the impact points?
Combine the two: Heat the steel, the primary load-bearing structural member of the tower, to the point where it becomes soft and almost plastic, and sheer weight will do the rest. As it began to collapse, the simple momentum of hundreds of thousands of tons of steel and concrete slamming down on each successive layer… well, that’s far more than the building was designed to withstand.
NO building COULD have withstood that.
As for the dust, well, there’s two buildings’ worth of concrete that have been pulverized… That undoubtedly created an enormous quantity of dust, that is simply kicked up and carried by the wind. I saw the news bits showing the office paperwork swirling in the winds… the same wind keeps stirring up the dust, helped along, unfortunately, by the constant activity. Right now, crews are shifting and shoveling, clearing paths through the rubble, searching for survivors or bodies…
Concrete dust, as far as I know, is no worse than “normal” dirt and dust. In large quantities, it can clog the alveoli in the lungs, but I don’t know of any long-term effects.
Dust masks are definitely recommended anyway.
Asbestos is only hazardous in small, breathable particulates- over time, it causes asbestosis, a lung disease, and it’s been linked to lung cancer. So here, definitely, wear a mask if you can, a wet rag if you have no other choice.
However, being built in the early seventies’, I don’t know how much asbestos the WT Centers contained. Wasn’t it being phased out of use at that point?