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View Full Version : If the WTC hadn't collapsed, how would they have fought the fire?


Quintas
09-11-2013, 05:05 PM
I watched the French documentary where they were in the lobby and sending firefighters up to assess the situation. The fire chiefs didn't really have time to come up with a plan before the buildings collapsed.

Assuming that they didn't collapse (impossible probably due to the nature of the construction) would there be another option aside from just letting it burn out? Are there hoses long enough to reach the impacted floors? If so, are the pumps on the trucks powerful enough to get water up that high?

drachillix
09-11-2013, 06:55 PM
Are there hoses long enough to reach the impacted floors? If so, are the pumps on the trucks powerful enough to get water up that high?

Buildings that size have a system of standpipes that run water to upper floors (you see them all the time in stairwells.) Larger buildings will actually have booster pumps that are triggered by the alarm systems to make sure there is water to the upper floors.

Hose connections are at the standpipes, so the water supply is as close as your nearest stairwell.

Your average fire engine might be able to get decent pressure for 10-15 floors, after that you need those pumps.

http://www.firehouse.com/article/10461617/standpipe-high-rise-packs-part-1

drachillix
09-11-2013, 06:58 PM
I was just an EMT who happened to go to fire academy and I could write you pages on high rise firefighting methods. One of the posters in the biz can probably give far more detailed answers.

Hello Again
09-11-2013, 07:53 PM
They didn't plan to fight the fire, apparently. From the top, the order went out as "rescue operation only."

However, its seems, from the NIST report that there was a huge element of "fog of war" with firefighters receiving garbled or vague orders, and who consequently showed up to fight a fire.

NIST report quoted here: Out of 9/11 Tragedy Came Change for FDNY (http://www.citylimits.org/news/article_print.cfm?article_id=4419)

drachillix
09-11-2013, 08:21 PM
They didn't plan to fight the fire, apparently. From the top, the order went out as "rescue operation only."

However, its seems, from the NIST report that there was a huge element of "fog of war" with firefighters receiving garbled or vague orders, and who consequently showed up to fight a fire.

NIST report quoted here: Out of 9/11 Tragedy Came Change for FDNY (http://www.citylimits.org/news/article_print.cfm?article_id=4419)

Fire operations unfold as follows

Rescue: get people out (and stuff if practical, see salvage)
Exposures: protect surrounding structures/threatened items
Containment: keep fire from spreading
Extinguish: put it out
Overhaul: make sure fire is out for good no smoldering bits left over.

So under the circumstances, with a massive rescue need, it was going to take 100% effort just to start extracting people as fast as possible.

drachillix
09-11-2013, 08:38 PM
NIST report quoted here: Out of 9/11 Tragedy Came Change for FDNY (http://www.citylimits.org/news/article_print.cfm?article_id=4419)

Didn't nitpick the whole article but one glaring technical fail popped out at me.

" To extinguish even a flaming half-floor of the WTC would have required, by NIST's calculations, 1,250 gallons of water a minute, a deluge that might take 10 engine companies to provide."

At ground level a typical fire engine can move 1000-1500gpm @ 150psi. Pushing up all those floors is a killer and would take several engines in series to crank up pressure to overcome gravity for a firefight at higher floors. Buildings like the WTC have a variety of pumps and water tanks scattered throughout the building for firefighting, problem is many of them, and or the water lines feeding them were damaged by the impact.

panache45
09-11-2013, 08:52 PM
Yes, but as the water extinguished fire in the higher floors, wouldn't excess water seep down to the floors below and help extinguish fire there? They wouldn't have to start from scratch with each floor.

Hello Again
09-11-2013, 08:52 PM
Are you saying its inaccurate because 10 isn't sufficient? FDNY has utrahigh pressure pumps.

Or did I misunderstand you?

drachillix
09-11-2013, 09:58 PM
Yes, but as the water extinguished fire in the higher floors, wouldn't excess water seep down to the floors below and help extinguish fire there? They wouldn't have to start from scratch with each floor.

Most of it ends up running down stairwells and elevator shafts.

drachillix
09-11-2013, 10:09 PM
Are you saying its inaccurate because 10 isn't sufficient? FDNY has utrahigh pressure pumps.

Or did I misunderstand you?

That much water is not a big deal....125GPM = one 1.5" standard interior attack line. Average fire engines can generate 1250 alone. Granted at higher pressures needed to pump up many floors IIRC the guideline is 5 psi per floor (395psi). So to get 1250GPM at 79th floor you would need some serious pumping power, but FDNY is equipped for that, high rise firefighting is what they do. The centrifugal pumps fire engines use can work in series. The process is referred to as tandem pumping

Hydrant to engine #1

pumping 1500 gpm@ 150 psi

engine #1 connects to intake side of engine #2 Who generates another 150psi to the same stream.

chain fire engines until desired pressure is achieved or hoses burst.

drachillix
09-11-2013, 10:14 PM
Individual engines can run higher pressures at a cost of flow rate, the 10 companies statement may be more about manpower to man 8-10 hoselines for the firefight, not about raw pumping power. FDNY has 95 engine companies on manhattan island.

Compared to my town Fresno, CA has 23 for a city of 600,000.

Werekoala
09-12-2013, 12:26 AM
I would assume this is a hard question to answer, since the fires weakening the steel supports was the ultimate cause of the collapse. Once the planes hit, collapse was inevitable. However, based on what our more experienced Board members have said, if the collapse was delayed then the plan would be to get as many people out as possible, which I assume means they would have beaten back at least some of the fires around/above the impact sites in the stairwell areas.

My WAG is that if they could have beaten back some of the blazes, they could have rescued some of the folks above the impact sites but would ultimately lose the battle to save the buildings. Less civilian casualties, the same or more casualties among the firefighters.

Chronos
09-12-2013, 02:12 PM
Less civilian casualties, the same or more casualties among the firefighters.
Well, the ideal would be to get all of the civilians out, and then once you've done that you get the firefighters out, too. Realistically, you probably start pulling the firefighters out at some point before the last civilian is out, though I'm not sure exactly what criteria the fire companies use for that.

drachillix
09-14-2013, 05:45 PM
Well, the ideal would be to get all of the civilians out, and then once you've done that you get the firefighters out, too. Realistically, you probably start pulling the firefighters out at some point before the last civilian is out, though I'm not sure exactly what criteria the fire companies use for that.

Firefighters will generally withdraw from a situation that they are sure will seriously injure them. Plenty take serious chances to rescue people who cannot extract themselves from a situation, but rule #1 is, go home to your family after your shift.

A Firefighters personal protective gear already allows them to survive conditions that would kill unprotected people in seconds.

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