Reply #29: "It did seem as though most of the material..."

[Carefulplease]

But it did seem as though most of the material was being pulverized and ejected from the building.

How would you know that? Do you know what a dust cloud comprising 200,000 tons of pulverized material looks like? How different is that from one comprising *only* 20,000 tons of material?

Analysis of dust samples around Ground Zero revealed that this dust contained as much gypsum as it did concrete. Let us consider just the concrete that made up the floors of the WTC Towers. This was 4 inches thick (lightweight concrete) in the tenant spaces and 5 inches thick (regular weight) in the core. Just assuming an uniform thickness of 4 inches for simplicity, let us suppose that just 10% of the concrete (and nothing else) was reduced to dust and ejected during the collapse. The footprint of one tower is about 1 acre. So 10% of the concrete reduced to dust would account for an average thickness of dust of one inch deposited on a net area of 88 acres (~66 football fields) of lower Manhattan. (That is 2towers*110floors*4inches*10%). I also assume the the dust is packed dense enough that its density is the same as the density of the slab it came from.

What would such an amount of dust look like if it were expelled from the falling towers? Are you quite sure that it really looked like more than 10 times this amount of dust has been expelled? How would you know?