# Debunk This Please

**URL:** <https://boards.straightdope.com/t/debunk-this-please/129336>\
**Category:** Factual Questions\
**Created:** [September 23, 2002, 8:27pm UTC](https://boards.straightdope.com/t/debunk-this-please/129336 "2002-09-23T20:27:30Z")\
**Posts on this page:** 3\
**Page:** 2

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**Author:** ![Johnny\_L.A](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/johnny_l.a/32/1084_2.png) [@Johnny\_L.A](https://boards.straightdope.com/u/Johnny_L.A)\
**Post date:** [September 24, 2002, 1:22pm UTC](https://boards.straightdope.com/t/debunk-this-please/129336/21 "2002-09-24T13:22:05Z")

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> [@](#):
>
> every floor contained tons of paperwork, paper-based acoustic ceiling tile, wooden furniture, foam-filled upholstery, etc. All of that stuff burns hot enough to weaken steel.

In addition, the towers were… well, _towers_. They stuck up high enough to be subjected to fairly steady wind. Plus when fires burn they draw in air from around them (remember the “fire storms” in WWII?). All of this wind undoubtedly made the fires burn hotter.

> [@](#):
>
> The core- and-shell structure of the WTC’s plan may not have been as sound as originally believed.

Well they _did_ withstand the impact of a larger aircraft than they were designed to.

As for the melting of steel, it’s already been pointed out that steel doesn’t have to melt to lose its integrity. It only has to be hot enough for it to bend.

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**Author:** ![Belrix](https://avatars.discourse-cdn.com/v4/letter/b/ed655f/32.png) [@Belrix](https://boards.straightdope.com/u/Belrix)\
**Post date:** [September 24, 2002, 3:56pm UTC](https://boards.straightdope.com/t/debunk-this-please/129336/22 "2002-09-24T15:56:15Z")

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I spoke, briefly, with a guy who built tall buildings once - pre 9/11.

I asked about the spray-on coating on steel beams. He explained that it was for two reasons. The first was rust protection. The second was fire protection.

Steel beams, he explained, in a fire can expand far enough to start shearing off the rivets holding the building together. After that the building simply collapses.

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**Author:** ![manhattan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/manhattan/32/7_2.png) [@manhattan](https://boards.straightdope.com/u/manhattan)\
**Post date:** [September 25, 2002, 12:32am UTC](https://boards.straightdope.com/t/debunk-this-please/129336/23 "2002-09-25T00:32:43Z")

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> [@](#):
>
> \*Originally posted by pilot141 \*  
> \*\* Any reliable sources for the actual construction issue? Did the WTC change materials 3/4 of the way up? \*\*

New York City banned spray-on asbestos in 1971, a year before the Big asbestos ban.

Accounts differ, but it appears that asbestos was used at least on the first 40 stories of tower one, and perhaps in some of tower two.

Most of it would have been long gone by now, as it has to be removed before re-doing a floor (so when tenant A moves out, there is remediation done as part of the construction preparing the floor for tenant B). This was pretty widely known (in general terms; again, the specifics are in dispute to this day), but I’m unaware of any evidence that OBL or his people considered this. From what it looks like, they just wanted to hit the towers and the Pentagon and the Capitol – the specifics of how many might die, whether buildings would collapse, etc., seem to have been, at most, secondary considerations.

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