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Clearly you have strong feelings on this issue but you have let them cloud
the issue. The Fire Department has no responsibility for the design
characteristics of buildings, some of which include the materials used, the
fire resistance ratings of the structural members and the structural
behavior under various conditions (fire, wind load, vibration, settlement,
shear, racking). The design requirements for such structures are firmly
embedded in specifications set forth by various design and testing firms
and adopted by local government agencies. Design engineering firms use
these guidelines for producing the building plans and specifications. City
building inspectors are charged with enforcement of the building code. The
Fire Department is eventually charged with the responsibility of
controlling fires and saving lives.
The fireproofing used on the steel in the WTC was most likely blown
completely off some of the structural members. Fireproofing comes in many
forms but to build a skyscraper, the accepted form is called spray-on
fireproofing. It is a mixture of cementious material mixed with fire
retardant. It is soft and can be scratched easily with your finger. It is
very likely that portions of that material were dislodged during the impact
of the plane and then the fire weakened the steel which led to the
collapse. Interior structural members, known as the core of the structure,
are often the most critical to the stability of the structure. That is
often where the diagonal bracing is located. The core is usually
fireproofed with cement masonry units (CMU), better known as concrete
blocks. These walls were also likely to have been knocked down at the time
of the impact. The underlying core steel members would then be totally
exposed. The collapse would then be unavoidable.
OK, so how do we build buildings to prevent this type of disaster. Very
simple, you define the type of blast and fire you anticipate and then build
the structure to meet these requirements. Based on what we have seen so
far, the sky scraper of the future would probably have 110 stories with 20
feet of reinforced concrete exterior walls with no windows. No matter what
you build, the terrorist has the ability to choose a weapon to attack the
structure you build. It is not a game you can ever win by redesigning the
buildings. You need to prevent the attack in the first place.
At 10:04 AM 9/22/01 -0700, you wrote:
>Hello Omega list,
>
>I'm writing mainly in response to Jack Griffin's
>statement in which he "condemns" F.D.N.Y. for not
>"knowing" that the World Trade Center buildings were
>going to collapse.
>
>I'd also like to shed some light on the purpose of,
>and limitations of fire sprinkler systems in response
>to Mark Brown's post.
>
>Jack Griffin wrote: Come on, the Fire Department
>should have thought about it. So if you won't condemn
>them I will. It was their job to know this (that the
>WTC’s would collapse). It was even in the stupid
>building design that the steel could only last 2 hrs
>at best in a fire. They screwed up royally…
>
>I am almost as stunned by the ignorance of this
>statement as I am by the fact that men would fly
>planes into buildings.
>
>Jack, I assure you that the F.D.N.Y. did, in fact,
>give some thought to the possibility of collapse.
>Allow me to educate you about why we have Fire
>Departments, and what their priorities are. The
>acronym L.I.P. adequately sums up the FD’s incident
>priorities. L.I.P.
>stands for: L Life safety. I Incident
>stabilization. P Property conservation.
>
>Upon arrival at the WTC incident, or any “typical”
>building fire, the Incident Commander must weigh the
>benefits versus the risks of sending firefighters into
>the building. Probably the most important question the
>IC has to consider is, “are there victims inside this
>structure who can be saved by aggressive interior
>tactics?” If the answer to this question is yes (as it
>was at the WTC incident), then any IC worth their salt
>will send firefighters into the building in an attempt
>to save lives.
>
>Basically, if there are lives to be saved,
>firefighters will put themselves in harms way to save
>those lives. Even if building collapse is a
>possibility. There was no way to “know” that the WTC
>towers would collapse so quickly.
>
>Although most people intuitively understand this, Jack
>apparently fails to get it.
>
>Imagine the following scenario. It’s 2:00 am, the
>kitchen, living room, and attic of your parent’s home
>are completely involved in fire, and the rest of their
>home is being charged with thick smoke. Your parents
>are asleep behind their closed bedroom door, and
>because of carbon monoxide, they fail to awaken at the
>sound of the smoke detectors going off. When the fire
>department arrives, they decide it’s too dangerous to
>try to enter the home and save your parents because
>there is a possibility the roof might collapse due to
>the lightweight truss construction in the attic. How
>would you feel about this fire department after your
>parents died in their bed of smoke inhalation, their
>bodies untouched by fire? At that point, do you think
>you might become a fan of aggressive fire department
>tactics?
>
>The F.D. at the WTC was faced with similar decisions,
>on a massively larger scale. What if the fire
>department didn’t go into the WTC towers, and they
>didn’t collapse, and thousands of people died in the
>fire? What would you think then?
>
>Jack, it’s easy to play Monday morning quarterback,
>after a ballgame or a tragic incident. Until you’ve
>worn a set of turnouts and crawled around in a burning
>building, you don’t have the right to condemn any fire
>department, because you don’t know what you’re talking
>about.
>
>
>Moving along…
>
>
>A typical fire sprinkler will discharge approximately
>25 - 35 gallons of water per minute when activated.
>Fire sprinklers are activated by a fusible link that
>opens the sprinkler head when the temperature reaches
>a given level. Only those sprinklers in direct contact
>with the fire's heat will react.
>
>When jumbo jets slammed into the WTC buildings, most,
>if not all of the sprinkler heads on multiple floors
>were probably activated. But it didn't make a single
>bit of difference. Why? Because 25 gpm per sprinkler
>head against TONS of burning jet fuel would have about
>the same effect as trying to put out a raging house
>fire by pulling out your Johnson and taking a whiz on
>it. The water would turn to steam the instant it
>exited the sprinkler head due to the immense heat.
>This is why airport crash fire/rescue apparatus are
>equipped with foam systems rather than simply water
>tanks.
>
>The tiny little sprinkler heads embedded in the
>ceilings we walk under everyday are designed to fight
>small Class A (wood, paper, etc.) combustible material
>fires. Common sense alone should tell us that these
>tiny little sprinkler heads are not designed to
>extinguish large commercial aircraft that are burning
>out of control.
>
>
>Hope this helps. Good day to all,
>
>-Lance
Bill Brower
Email: 1000mileman@xxxxxxxxxxxxxx
Web Site: insideedge.net
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