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[bill smith]

After following this thread from inception, it appears neccessary to weigh in regarding High Rise fires, heat generated, and extinguishment of those fires..

I am an Operations Fire Captain assigned to a Heavy Rescue in the 5th largest fire Department in North America. I have almost 27 years of firefighting, technical rescue and HUSAR (Heavy Urban Search And Rescue) experience, and have fought thousands of fires, great and small, over my career.

My hat is off to the brave and selfless brothers of the FDNY and their sacrifice. So many have paid the ultimate price. Fellow firefighters worldwide are eternally grateful for their pioneering efforts in fire suppression over the last 180+ years.

Some basic facts regarding fires, heat, and water used to extinguish high rise fires need to be laid out. The professional fire fighters here already know this stuff, but for those of you who have never been face to face with a fire in a high rise office building, I want to give you a taste of what it's like.

Let's begin with 'fire load'. Fire Load is the amount of combustible matter present that can act as a fuel to feed a fire. This includes paint and floor covering.
For a standard office building, the NFPA Handbook, 20th edition, calculates office fire loads at around 10 lbs/sq ft. For file storage areas the load goes to almost 17 lbs/sq.ft. For our purposes we'll use 10 pounds/ sq. ft.
When that fire load burns, we get heat, so we'll use BTU's to measure it here. Everyone can relate to BTU's, since your backyard gas grill has heat output measured in BTU's. The average gas grill outputs around 50,000 btu's at full flame.
The NFPA tells us that 17,000 btu's are created when one pound of average office fireload burns. Since we already know our office has a fireload of 10 pounds per square foot, our minimum heat output will be 170,000 btu's or over 3 backyard BBQ's at full bore per square FOOT
So, take the figure above, and multiply it by one hundred for just a 10 foot x 10 foot area of office, and you begin to understand the heat produced by even a very small office building fire. Surround that fire with a reinforced concrete box, and where do all those BTU's go?
They go into evaporating the water directed at it by the fire hose, and turning it into steam. In my professional opinion, in an office building with a 50'x 50' area burning, it is highly unlikely that any of the water directed at the fire from a 2 1/2 inch line will reach the seat of the fire, evaporating as it approaches the fire due to the intense heat generated.
Several 2 1/2 inch lines or a monitor with multiple 2 1/2 inlets would be needed for such an area of fire.
As you can well imagine, put 3 or 4 of these fires on any given floor, and the resources needed to fight just one floor of high rise office building fires is considerable.

As one can see from the above example, hand held fire extinguishers are not an option. If we need to delve into the actual purpose of hand held fire extinguishers, I can deal with that in a separate post.

I think NIST estimate a combustible load of only about 4 pounds per square foot. You estimate 10 pounds. Who is right ?

 

[leftysergeant]

You lit off thermite in a gay bath house?

Got some crud on my glasses and have a hard time proof reading. Spell checker, when it runs for me at lal, doesn't catch words that are spelled right but in the wrong context.

 

[PhantomWolf]

I think NIST estimate a combustible load of only about 4 pounds per square foot. You estimate 10 pounds. Who is right ?

I think the general concensus these days is the NIST underestimated the fire loading. Even with the lower loading the senario resulted in a collapse. Of course with a higher loading, less of the fire retardant would be required to be damaged to get the same result.

 

[Senenmut]

Ummm no as this assessment of the impending collapse provides NO information on what started the collapse initiation.

How would an assessment that the building was probably going to collapse from their readings help nist determine the exact reason behind the collapse?

Trying to conflate these readings and information to the NIST report is at best a faulty comparision if not a complete red herring.

If you want to find out about those readings, feel free to file a FOIA request and find out about them. While those readings would no doubt be a snapshot of the events of the morning, they don't change the basic facts of 9/11.

it must of showed something if the engineer said you have 5 hrs before wtc7 collapses and he was "right on the money" about the timeframe. so yeah, ill try and file a foia request. i was hoping the fireman here would know a way to get that without going through hoops.

 

[tsig]

I think teltale tom is parodying the truthers.

The name might be a giveaway.

 

[tsig]

No he's a Shill pretending to be a Truther in order to try and make Truthers in general look bad. I find it hilarious. lol

You can't tell the players without a scorecard. Who's under the bus or driving it?

I think the bridge is out and we don't know how many got off the bus.

 

[tsig]

in those 20 yrs, have ya ever encountered fireproofing that had "melted into a glassy residue?"

Have you ever encountered fireproofing?

 

[Senenmut]

If you were paying attention, and actually READING what is posted, you would have seen his post.

Fireproofing doesn't, by definition "melt", but more degrade.

Fireproofing is more about how long it will last in a fire. Fireproofing is not designed primarily to save a building, but to save its occupants.

from mackeys quote:
" ....the melting temperature of the fireproofing is probably around 1300oC, lower than the steel it's supposed to protect. But that's not the point. The point is that the heat flow through the material is very low. If the surface melts or otherwise falls off, it exposes new material underneath that is still at a lower temp."

so he thinks the melting point of fireproofing is....what again?

 

[triforcharity]

I'm not sure why the last place I was at called it SCBE. I think most are familiar with SCBA. I suppose it's to distinguish it from SCUBA, but I don't know. I see most refer to it as SCBA.

SCBE, SCBA, same exact thing. SCUBA-NOT the same, obviously.

It just depends on the department. In my department, we call a large truck with a huge ladder attached a "Truck". Like, for instance, "Truck 44 respond to.........." We also have a truck with a large ladder, but also has a platform attached to the end, its refered to as an "Aerial"

Just depends. I call it SCBA.

 

[triforcharity]

it must of showed something if the engineer said you have 5 hrs before wtc7 collapses and he was "right on the money" about the timeframe. so yeah, ill try and file a foia request. i was hoping the fireman here would know a way to get that without going through hoops.

Nope. You will have to FOIA request that. I would not suggest starting the letter with the following. " You incompetant idiots..." I don't think you will get very far. PS. Make sure you ask the correct people. Truthers LOVE to yell about the DOD not releasing the videos from the hotels accross from the Pentagon. Please don't make that same mistake.

 

[Senenmut]

For the sake of this thread, what possible reason do you have to demand what you ask for?

It's been established that trained professionals anticipated the collapse.

Thread closed.

are ya sure about that. give me a name to those "trained pros". we have no data from those tests they ran. plus, they got the confirmation that it would fall in 5 hrs from an engineer from within the OEM and he was "right on the money."

did trained professionals anticipate the wtc collapses or was it the insight on a single engineer that we have no name for.

in a firefighters oral history peruggia states:

"We were always told
by everyone, the experts, that these buildings could
withstand direct hits from airplanes. That's the way
they were designed. They went through all of this
architectural stuff, way beyond the scope of my
knowledge.
It was hit by an airplane. That's okay.
It's made to be hit by an airplane. I mean I think
everyone may have believed that. We were all told."


And tell me who said those building would collapse.....it was the "engineer" with no name?

 

[triforcharity]

from mackeys quote:
" ....the melting temperature of the fireproofing is probably around 1300oC, lower than the steel it's supposed to protect. But that's not the point. The point is that the heat flow through the material is very low. If the surface melts or otherwise falls off, it exposes new material underneath that is still at a lower temp."

so he thinks the melting point of fireproofing is....what again?

The spray foam fire resistant coating will, for arguments sake, melt. Yes. But, not by true definition. He explained what it does later on, I believe in the very same post. I could be wrong though.

PS. Do you understand how the "fireproofing" works in a building, and what its function is??

Also, do you call a vest that a police office wears to protect him from bullets a bullet proof vest?? Yes, most do. But, alas, it is not bulletproof.

 

[Senenmut]

The spray foam fire resistant coating will, for arguments sake, melt. Yes. But, not by true definition. He explained what it does later on, I believe in the very same post. I could be wrong though.

PS. Do you understand how the "fireproofing" works in a building, and what its function is??

Also, do you call a vest that a police office wears to protect him from bullets a bullet proof vest?? Yes, most do. But, alas, it is not bulletproof.

well that is pretty interesting that fireproofing melts at 1300C. what was the max temp the nist said the wtc experienced? wasnt it around 1000c?

 

[triforcharity]

IIRC, it was around 1800f. I could be wrong on this.

But, leave this in a pile of smoldering debis for months, and what do YOU think will happen to it??

This answer has to do with something we have already discussed. Think real hard now.

 

[Senenmut]

I've seen many things "melted to a glassy residue" over the years. Was some of it fire-retardant¹? I'd have to ask the Fire Scene Investigators we were assisting as I have never specifically looked for "retardant turned to glassy residue".

I can tell you the most common problem I've seen with fire-retardant on structural steel (other than shoddy application) is it's friableness. It can and does come off in patches exposing steel to heat.

in your 20 yrs, have ya ever run accross A36 steel that looked like "swiss cheese" coming from an ordianary office fire. this fire could have sat in a pile burning for 9 days or so???

 

[Senenmut]

IIRC, it was around 1800f. I could be wrong on this.

But, leave this in a pile of smoldering debis for months, and what do YOU think will happen to it??

This answer has to do with something we have already discussed. Think real hard now.

what temps did aviris see 5 days later (not months later) ??? i know mackey knows this one.........its not 1300C. do ya think it will still melt at that point or are we going to have to have a higher temp?

 

[Senenmut]

IIRC, it was around 1800f. I could be wrong on this.

sounds about right.

 

[triforcharity]

what temps did aviris see 5 days later (not months later) ??? i know mackey knows this one.........its not 1300C. do ya think it will still melt at that point or are we going to have to have a higher temp?

IT DOESN'T MATTER!! Really, it doesn't. Go back, and read the thread. Pay special attention to mine, and mackey's posts. There are others, im sure. But, I do know we have both mentioned it.

 

[triforcharity]

in your 20 yrs, have ya ever run accross A36 steel that looked like "swiss cheese" coming from an ordianary office fire. this fire could have sat in a pile burning for 9 days or so???

What other "ordinary office fires" sit on the ground, in HUGE piles, burning for months, with a high content of sulfer??

It was not ordinary in the least bit.

 

[Senenmut]

Every building that begins to lean in one direction, and continues to progressively tilt more & more in that same direction WILL collapse. There are zero exceptions to this rule.

This is completely independent of the cause of the leaning.

If the RATE of lean is slowing, then it may or may not collapse. It remains standing only if the rate goes to zero before collapse.

If the RATE of leaning is approximately constant, then it will collapse in a time that can be measured in minutes to centuries (Tower of Pisa).

If the RATE of leaning is increasing, then the answer is "soon".

One of the firemen ordered the transit put on the building as soon as he got there after WTC1 collapsed & he saw the damage. They watched the building lean from that time (~11 am) until mid afternoon. The rate was not slowing down. Ergo, it's collapse was certain, unless something changed.

I heard that the rate of leaning started increasing around 2 o'clock. This transit data is precisely the piece of information that told the firemen that WTC 7 would likely collapse.

There is nothing mysterious or insidious about this.

tom

thank you for this information. but i do have to ask to see a link where ya got this information.
please explain: "This is completely independent of the cause of the leaning." (sounds like you are wiggling your way out of this data being important to the nist).

what was this "rate of lean" from 11 to mid afternoon and how was it measured. what other studies have been conducted in the past that deal with the amount of "lean" in regards to total collapse? could a FOIA request get this information?