Metatheory and the NIST report

[Myriad]

Then what did they mean by this:

“The principal combustibles on the fire floor were workstations. The total combustible fuel load on the WTC floors was about 4 lb/ft2. Higher combusted fuel loadings resulted in slower fire spread rates that did not match the patterns observed in the photographic evidence. Under these higher combusted fuel loadings, the fires likely would not have reached the south side of WTC 1 in the time needed to cause inward bowing and collapse initiation.”(NCSTAR 1, 183)

How much higher?

“Simulations performed with doubled fuel loads slowed the fire spread well below the observed rates. Combined with the above results, this suggested that the estimated overall combustible load of 4 lb/ft2 was reasonable.”(NCSTAR 1, 129)(emphasis added)

Either they mean what they say here and the increased fuel load would not produce a collapse in the given time restraints, or none of their estimates are meaningful. Which is it?

These higher fuel loadings also "did not match the patterns observed in the photographic evidence." Either they meant what they said, or they didn't. If they did, you're plain wrong. If not, then how do we know if anything they said is useful or not?

Double the fuel load would not produce a collapse in the given time frame or match the patterns observed in the photographic evidence.

Where is it stated that a 5 lbs/ft^2 fuel load did not produce a collapse in the given time frame or did not match the patterns observed in the photographic evidence?

Exactly. Only when they increased the fuel loads did they get collapse initiation, but at the expense of matching observable patterns of fire-spread rates. This is one of the reasons they give for substantiating their estimate of 4 lb/sq ft.

Where is it stated that a 5 lbs/ft^2 fuel load did not produce a collapse in the given time frame or did not match the patterns observed in the photographic evidence?

Respectfully,
Myriad

 

[jay howard]

How much higher?

“Simulations performed with doubled fuel loads slowed the fire spread well below the observed rates. Combined with the above results, this suggested that the estimated overall combustible load of 4 lb/ft2 was reasonable.”(NCSTAR 1, 129)(emphasis added)




Double the fuel load would not produce a collapse in the given time frame or match the patterns observed in the photographic evidence.

Where is it stated that a 5 lbs/ft^2 fuel load did not produce a collapse in the given time frame or did not match the patterns observed in the photographic evidence?




Where is it stated that a 5 lbs/ft^2 fuel load did not produce a collapse in the given time frame or did not match the patterns observed in the photographic evidence?

Respectfully,
Myriad

Is 5 higher than 4?

 

[Myriad]

Is 5 higher than 4?

Yes.

4.001 is also higher than 4.

Do you think that means that a fuel load of 4.001 lbs/ft^2 would have resulted in slower fire spread rates that did not match the patterns observed in the photographic evidence?

Where is it stated that a 5 lbs/ft^2 fuel load did not produce a collapse in the given time frame or did not match the patterns observed in the photographic evidence?

Respectfully,
Myriad

 

[jay howard]

Yes.

4.001 is also higher than 4.

Do you think that means that a fuel load of 4.001 lbs/ft^2 would have resulted in slower fire spread rates that did not match the patterns observed in the photographic evidence?

Not likely. It's not an appreciable difference. The difference between 4 lbs/sq ft and 5 lbs/sq ft is the difference between 60 tons per floor to 75 tons per floor of combustible material. That, as far as I can ascertain from the reports, is the next "higher" amount of fuel used in the simulations as well as an appreciable difference.

Do you see some reason why their words regarding the failure of "higher fuel loads" to match observable patterns" does NOT mean 5 lbs/sq ft?

“The principal combustibles on the fire floor were workstations. The total combustible fuel load on the WTC floors was about 4 lb/ft2. Higher combusted fuel loadings resulted in slower fire spread rates that did not match the patterns observed in the photographic evidence. Under these higher combusted fuel loadings, the fires likely would not have reached the south side of WTC 1 in the time needed to cause inward bowing and collapse initiation.”(NCSTAR 1, 183)

Higher than what? You seem to agree that they mean higher than 4 lbs/sq ft, but you somehow want to skip the 5 lbs/sq ft value because 4.001 lbs is greater than 4 lbs? You've got to take a ridiculous stance in order to make your position make sense. Either they mean what they say, or they do not. Which is it?

Where is it stated that a 5 lbs/ft^2 fuel load did not produce a collapse in the given time frame or did not match the patterns observed in the photographic evidence?

Respectfully,
Myriad

In the above quote. 5 lbs is higher than 4 lbs, and it is, as far as I can tell, the next higher value they used in the simulations. If they meant higher fuel loading than 5 lbs/sq ft did not produce the collapse, why didn't they say that? If they wanted to say 5 lbs/sq ft was a reasonable estimate of fuel load for the WTC towers, why did they say this:

“NIST estimated the combustible fuel loading on these floors to have been about 4 lb/ft2 (20 kg/m2), or about 60 tons per floor. This was somewhat lower than found in prior surveys of office spaces. The small number of interior walls, and thus minimal amount of combustible interior finish, and the limited bookshelf space account for much of the differences.”(NCSTAR 1, 77)

 

[Complexity]

jay howard - What precisely do you mean by the term 'metatheory'?

 

[Myriad]

Do you see some reason why their words regarding the failure of "higher fuel loads" to match observable patterns" does NOT mean 5 lbs/sq ft?

Yes, because they made a very similar comment specifically in refernce to double the fuel load earlier in the report. In discussing a parameter with a high range of uncertaintly, "higher" meaning "approximately double" can be quite reasonable.

But we don't have to guess about how much higher they meant by "higher" in the statement about higher fuel loads not matching the observable patterns. They did runs of the simulation at 5 lbs/ft^2, didn't they? (Of course they did, that's what you are complaining about!) So when they actually ran the simulation with that value, did the simulated fire behavior match the patterns observed in the photographic evidence, or not?

Respectfully,
Myriad

 

[cmcaulif]

Do you see some reason why their words regarding the failure of "higher fuel loads" to match observable patterns" does NOT mean 5 lbs/sq ft?

because they essentially say it:

The fire simulation results for both Case A and Case B were similar, indicating only a modest sensitivity to the fuel load and the degree of the aircraft-generated damage. This was because, in general, the size and movement of the fires in WTC 1 were limited by the supply of air from the exterior windows. Since the window breakage pattern was not changed in Case B, the additional and re-distributed combustibles within the building did not contribute to a larger fire. The added fuel did slow the spread slightly because the fires were sustained longer in any given location.

So to summarize, a 100 percent increase in the fuel load slows the spread well below the observed rates, but a 25 percent increase is similar to the base case. These both remain within the experimentally determined gas temperatures as well.

"higher fuel load" does not mean automatic failure, as we see, the load needs to be increased by a great deal more than 25 percent for it to have an effect that would be critical to the collapses.

 

[beachnut]

jay howard - What precisely do you mean by the term 'metatheory'?

It is a truther smoke screen, trying to show he can apply some physiological junk to discredit NIST while ignoring the facts that 9/11 happen with an impact, fire, and collapse of the WTC. He is a Jones thermite fan, who refuses to admit it, but lets it leak as he posts and shows his failure to apply his own methods properly.

 

[question mark]

hello all, I was just wondering if anyone could tell me when the final NIST report will eventually be released?

The last I heard it would be in the spring of this year.

As far as I'm aware it still hasn't been released, is this the case?

Thanks in advance.

 

[cmcaulif]

QM, if you are referring to the NIST report on building 7, it was pushed back, again, to the end of the year. Who knows if it will ever see the light of day . The final report on 1 and 2 was released in 05 though. here is the NIST website for all the announcements and documents on the WTC:

http://wtc.nist.gov/

 

[question mark]

Pushed back again you say, oh well, thanks for your help.

 

[jay howard]

So to summarize, a 100 percent increase in the fuel load slows the spread well below the observed rates, but a 25 percent increase is similar to the base case.

Where do you get the notion that a 25% increase over a baseline estimate is "similar to the base case"? Obviously, you're not trying to argue that 5 lb/sq ft is their estimate of fuel load. Given that they substantiate 60 tons per floor several times, why do you think the increase is warranted? If they said, "a reasonable fuel load was between 60-75 tons per floor", then your statement would follow, however, they do NOT say that.

Don't misunderstand me, I do believe they were warranted to adjust the simulation inputs, but to increase them 25% with no clear justification, and then to pin their entire theory on those increased results is very far from scientific. Increase them 10% or maybe 12%, but if the fuel load estimation seems well-founded, why increase it further? They give no reason why 4 lb/sq ft is not a reasonable estimate.

Can you find anywhere where they say "5 lbs/sq ft was a reasonable fuel load for the towers" or "4 lbs/sq ft is NOT reasonable"?

These both remain within the experimentally determined gas temperatures as well.

Temperature is not the issue. Like Eagar & Musso say, if you put another log on the fire, it doesn't burn hotter, just longer. Fire-spread rates are the issue on this one. And as i've pointed out several times, NIST makes clear that

"Higher combusted fuel loadings resulted in slower fire spread rates that did not match the patterns observed in the photographic evidence. Under these higher combusted fuel loadings, the fires likely would not have reached the south side of WTC 1 in the time needed to cause inward bowing and collapse initiation.”(NCSTAR 1, 183)

Notice they don't say "double the fuel loadings..." here. If they meant to say that, they would have said that.

And they substantiate the slower fire-spread rates with higher-combustible loads:

"Since the window breakage pattern was not changed in Case B, the additional and re-distributed combustibles within the building did not contribute to a larger fire. The added fuel did slow the spread slightly because the fires were sustained longer in any given location."(NCSTAR 1, 129)

"higher fuel load" does not mean automatic failure, as we see, the load needs to be increased by a great deal more than 25 percent for it to have an effect that would be critical to the collapses.

Are you suggesting that NIST's theory is lacking? Where did this extra fuel you are implying come from? What do you mean "the load needs to be increased by a great deal more than 25 percent for it to have an effect that would be critical to the collapses"?

 

[jay howard]

jay howard - What precisely do you mean by the term 'metatheory'?

Theory about how to sift the theoretical wheat from the chaff. See the first post for a more complete explanation.

 

[jay howard]

Yes, because they made a very similar comment specifically in refernce to double the fuel load earlier in the report. In discussing a parameter with a high range of uncertaintly, "higher" meaning "approximately double" can be quite reasonable.

But we don't have to guess about how much higher they meant by "higher" in the statement about higher fuel loads not matching the observable patterns. They did runs of the simulation at 5 lbs/ft^2, didn't they? (Of course they did, that's what you are complaining about!) So when they actually ran the simulation with that value, did the simulated fire behavior match the patterns observed in the photographic evidence, or not?

Respectfully,
Myriad

If they ONLY meant "double", then why did they say "Higher combusted fuel loadings resulted in slower fire spread rates..." in the sentence from pg 183? If they ONLY meant "double" they would have said so in that spot. That was their opportunity to make that distinction.

But they chose to say "higher" and we know 5 is indeed higher than 4. Why do I actually have to explain this to you? Either they meant what they said or they didn't. Either words mean whatever is convenient or they are substantiated by their context. Which is it?

Again, did NIST produce good estimates and ignore them, or were their estimates poor from the start?

 

[cmcaulif]

Where do you get the notion that a 25% increase over a baseline estimate is "similar to the base case"?

I realize you are fond of ignoring what others post, but reread the bit I quoted from the NIST, they say that exactly.

Obviously, you're not trying to argue that 5 lb/sq ft is their estimate of fuel load. Given that they substantiate 60 tons per floor several times, why do you think the increase is warranted? If they said, "a reasonable fuel load was between 60-75 tons per floor", then your statement would follow, however, they do NOT say that.

Don't misunderstand me, I do believe they were warranted to adjust the simulation inputs, but to increase them 25% with no clear justification, and then to pin their entire theory on those increased results is very far from scientific. Increase them 10% or maybe 12%, but if the fuel load estimation seems well-founded, why increase it further? They give no reason why 4 lb/sq ft is not a reasonable estimate.

Can you find anywhere where they say "5 lbs/sq ft was a reasonable fuel load for the towers" or "4 lbs/sq ft is NOT reasonable"?

I see, so you think an increase is justified, but you don't think a 25 percent increase is justified even though they explicitly say case a and b were similar, indicating a limited sensitivity to the fuel load increase. I get the feeling that your belief that the NIST report is junk science is unfalsifiable.

Temperature is not the issue.

snip

erm, I know, that is what I meant to point out.

Are you suggesting that NIST's theory is lacking? Where did this extra fuel you are implying come from? What do you mean "the load needs to be increased by a great deal more than 25 percent for it to have an effect that would be critical to the collapses"?

In order for it to produce a result that would be outside experimental uncertainty, as well as outside the observed rates of fire spread, with the range of experimental uncertainty associated with that, the fuel load would would have to be increased by a great deal more than 25 percent, since this produced results that were similar to case a.

 

[jay howard]

I realize you are fond of ignoring what others post, but reread the bit I quoted from the NIST, they say that exactly.

Quote where they say

"a reasonable fuel load was between 60-75 tons per floor"?
or
"5 lbs/sq ft was a reasonable fuel load estimate for the towers"?
or
"4 lbs/sq ft was not a reasonable fuel load estimate"?

As has been pointed out ad nauseum for us both is that they explicitly justified the 4 lbs/sq ft estimate several times. In addition to this, they never give any explicit justification for increasing this estimate other than to "to create a more severe fire." They also state in no uncertain terms that in regard to WTC 1, when they increased the fuel load above 4 lbs/sq ft, the observations did not match the available evidence AND the fires did not reach the south side in time to initiate the collapse.

Did they mean to exclude 5 lbs/sq ft in that statement? Only if words do not mean what they normally mean.

If they had reason to believe they underestimated the fuel load by 25%, they give no indication. So, how 5 lbs/sq ft suddenly becomes implicit in a "probable range of gas temperatures" in the simulations is nothing more than an arbitrary assumption.

I see, so you think an increase is justified, but you don't think a 25 percent increase is justified even though they explicitly say case a and b were similar, indicating a limited sensitivity to the fuel load increase. I get the feeling that your belief that the NIST report is junk science is unfalsifiable.

I gave very clear statements of what would count as a counterexample to my interpretation. There are 3 unambiguous statements above. Is there some reason those would not count as tests of my theory?

In order for it to produce a result that would be outside experimental uncertainty, as well as outside the observed rates of fire spread, with the range of experimental uncertainty associated with that, the fuel load would would have to be increased by a great deal more than 25 percent, since this produced results that were similar to case a.

For the life of me, I do not understand what you are saying here. No sarcasm.

"In order for it [the simulation] to produce a result outside experimental uncertainty, [how do you get outside uncertainty and why do you want to get there?] as well as outside the observed rates of fire spread, [don't you want to be within observed rates of fire spread?], with the range of experimental uncertainty associated with that, the fuel load would have to be increased by a great deal more than 25 percent, [why?], since this [what? the increase outside the observed rates?] produced results that were similar to case a. [The whole point of differentiating 4 lbs/sq ft was that increasing the fuel load did not match observable fire spread rates.]

I may have slaughtered your meaning. If so, please clarify.

 

[cmcaulif]

Quote where they say

"a reasonable fuel load was between 60-75 tons per floor"?
or
"5 lbs/sq ft was a reasonable fuel load estimate for the towers"?
or
"4 lbs/sq ft was not a reasonable fuel load estimate"?

As has been pointed out ad nauseum for us both is that they explicitly justified the 4 lbs/sq ft estimate several times. In addition to this, they never give any explicit justification for increasing this estimate other than to "to create a more severe fire." They also state in no uncertain terms that in regard to WTC 1, when they increased the fuel load above 4 lbs/sq ft, the observations did not match the available evidence AND the fires did not reach the south side in time to initiate the collapse.

you are just posting false information. They state case a and case b were similar, indicating limited sensitivity to the fuel load increase. Why do you keep ignoring that? And why do you keep ignoring that it was when the fuel load was doubled, it did not match observed evidence and did not reach the south side in time for collapse?

Yes they justify the 4 lbs/sq ft estimate, but it is an estimate, and numerous posters have given you various explanations for the fuel load increase, with your responses ranging from 'so what' to 'so effing what,' while you still seem to believe that a statement that applied to a doubled fuel load applied to case B, which they explicitly state was similar to case a.

If they had reason to believe they underestimated the fuel load by 25%, they give no indication. So, how 5 lbs/sq ft suddenly becomes implicit in a "probable range of gas temperatures" in the simulations is nothing more than an arbitrary assumption.

The fuel load also affects the evolution of the fire, and the increase of fuel load increased the duration of the fires in the core area, as they say on page 78 of NCSTAR1-5F. This has been discussed as nauseam.

I gave very clear statements of what would count as a counterexample to my interpretation. There are 3 unambiguous statements above. Is there some reason those would not count as tests of my theory?

They could, but you of course know they can't be found. Numerous posters have explained the fuel load increase despite the fact that you insist on factual errors to be true, as have been pointed out above. You started a thread with no intention of listening to what others might say.

"In order for it [the simulation] to produce a result outside experimental uncertainty, [how do you get outside uncertainty and why do you want to get there?] as well as outside the observed rates of fire spread, [don't you want to be within observed rates of fire spread?], with the range of experimental uncertainty associated with that, the fuel load would have to be increased by a great deal more than 25 percent, [why?], since this [what? the increase outside the observed rates?] produced results that were similar to case a. [The whole point of differentiating 4 lbs/sq ft was that increasing the fuel load did not match observable fire spread rates.]

I may have slaughtered your meaning. If so, please clarify.

you are under the mistaken impression that the 25% increase in fuel load did not match the observed rates of spread, slowing the fire enough so that it would not reach the south side to cause bowing. This is clearly false because that statement applies to a doubling of the fuel load, and they state that case A and B were similar. As they note, this indicates a limited sensitivity to the load increase, rather than the large sensitivity that you mistakenly imply.

You seem to have no interest in correcting this error of fact, so I will just bow out of the conversation here, there are plenty of posts from a variety of posters for you to re ignore on the topic.

 

[TellyKNeasuss]

You started a thread with no intention of listening to what others might say.

If jay howard doesn't consider our explanations satisfactory, he can always write to the engineering college at a local public university. Of course, that assumes that jay howard really does want to know if the manner in which NIST used the fire simulation results is acceptable in the engineering community.

 

[jay howard]

you are under the mistaken impression that the 25% increase in fuel load did not match the observed rates of spread, slowing the fire enough so that it would not reach the south side to cause bowing. This is clearly false because that statement applies to a doubling of the fuel load, and they state that case A and B were similar. As they note, this indicates a limited sensitivity to the load increase, rather than the large sensitivity that you mistakenly imply.

You seem to have no interest in correcting this error of fact, so I will just bow out of the conversation here, there are plenty of posts from a variety of posters for you to re ignore on the topic.

Of course you will. However, it doesn't change the fact that if they meant to say that ONLY double fuel loads did not match fire-spread rates and observables, they would have said that.

The fact is they said "HIGHER", not just "double" to differentiate the fire-spread rates and inability to match observables. Higher than what?

Higher than 4 lbs/sq ft.

Is 5 lbs/sq ft higher than 4 lbs/sq ft?

“Simulations performed with doubled fuel loads slowed the fire spread well below the observed rates. Combined with the above results, this suggested that the estimated overall combustible load of 4 lb/ft2 was reasonable.”(NCSTAR 1, 129)

You can repeat this claim until the end of time, but it will still not be in contradiction to the claim that,

"...Higher combusted fuel loadings resulted in slower fire spread rates that did not match the patterns observed in the photographic evidence. Under these higher combusted fuel loadings, the fires likely would not have reached the south side of WTC 1 in the time needed to cause inward bowing and collapse initiation.”(NCSTAR 1, 183)

If it were true that only 8 lbs/sq ft did not match the photographic evidence as well as the fire-spread rates, they would have said so in the above quote. Instead they say "higher" twice. "Higher" is a relative term. In this context, the word is used against 4 lbs/sq ft. Since 5 lbs/sq ft is higher than 4, there can be no confusion (except that which we wish to posit) that 5 lbs/sq ft also did not match the photographic evidence and the fire-spread rates.

This is clear. Any other interpretations rely on a degree of speculation that is not substantiated by the report. Like I said before, if you can find a quote that says one of these things, you might be right:

"a reasonable fuel load was between 60-75 tons per floor"
or
"5 lbs/sq ft was a reasonable fuel load estimate for the towers"
or
"4 lbs/sq ft was not a reasonable fuel load estimate".

But you freely admit this verbiage is not to be found in the reports. So, you must pull an unsubstantiated interpretation out of your colon to avoid conceding the fact that 5 lbs/sq ft is not supported by any of the NIST literature as a reasonable fuel load estimate. Not only is 5 lbs/sq ft not supported, 4 lbs/sq ft is explicitly supported several times for several reasons.

The facts remain that 5 lbs/sq ft is not a reasonable estimate by their own words, AND they pin their entire theory on a simulation that uses 5 lbs/sq ft as the definitive amount to initiate collapse. Struggle as you might to weasel a coherent interpretation out of the NIST report, you cannot get around these facts.

Again, this is not an inconsequential issue. The entire NIST collapse theory rests on this assumption. Without substantiating 5 lbs/sq ft, you and everyone else who believes NIST is engaging in belief-without-reason, or "faith" as it is commonly called. I don't have to make anything up to get the interpretation I have. Nor do I have to stretch the meaning of any words or take any of their sentences out of context. All I had to do was read carefully and take their words to mean what they always mean.

You must stretch their meanings beyond reason in order for your interpretation of the information to congeal. Is this not exactly the problem you have with the "twoofer" movement?

 

[Myriad]

NIST ran cases of the simulation with fuel loading of 5 lbs/ft^2.

Did the simulated fire behavior in those runs match the patterns observed in the photographic evidence, or not?

Respectfully,
Myriad