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RE: Questions about the Events of September 11 (off topic)

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Karen,

That was in interesting experiment.  The difference is that the Jet A
ignited immediately upon impact, and could not "soak" into the fireproofing.

If a structure is perceived to be subject to a fuel fire, the fireproofing
is significantly different.  In the petro-chemical industry, they use
intumescent coatings.  They will not soak up anything, are resistant to
abrasion, have good adhesion, and protect the steel from fire.

The FEMA 403 team had some excellent fire engineers on board including fuel
fire experts .  The 6 to 8 minutes was not correct.  I polluted my memory
with some off line discussions with the fire guys.  All of the fuel fire
experts agreed that the Jet A flashed off in a maximum of 5 minutes (Upper
bound per FEMA 403, Sect. 2.2.1.2).

Regards,
Harold O. Sprague

> -----Original Message-----
> From:	Casano, Karen [SMTP:Karen.Casano(--nospam--at)dgs.ca.gov]
> Sent:	Tuesday, November 12, 2002 12:45 PM
> To:	'seaint(--nospam--at)seaint.org'
> Subject:	Re:  Questions about the Events of September 11 (off topic)
> 
> 
> 
> Harold Sprauge wrote:
> .....<snip> ..The plane fuel load was the source of multiple fire
> ignitions,
> and the fuel
> / air explosion, and impact removed a lot of fireproofing from the
> trusses.
> The fuel itself flashed off in about 6 to 8 minutes.  From that point on,
> office furnishings were the source of the fire.  The fire was NOT hot
> enough
> to melt the steel, but it was hot enough to significantly reduce the steel
> strength for the unprotected steel trusses.  <snip>....
> 
> 
> I have not read the FEMA document, so please forgive me if I reveal any
> significant ignorance.  A friend and I conducted a crude but interesting
> backyard experiment the other day to test his idea.  We took a piece of
> fireproofing from a jobsite, doused it with lighter fluid to similate jet
> fuel and set it on fire.  The fireproofing sample soaked up a LOT of fluid
> before it was saturated - it seemed to be an excellent sponge, and it
> burned
> for about 20 minutes.  I wonder if anyone considered the idea that the
> fireproofing may have actually helped to hold a burning fire directly on
> the
> steel?  
> 
> -karen casano
> 

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