This paper will discuss the evidence related to the official investigations conducted by the National Institute of Standards and Technology (or NIST), whose reports comprise the final official explanation for what happened at the World Trade Center on September 11, 2001.
Before I discuss the NIST reports, however, it is important to consider the low probability that the only three instances of a skyscraper suffering complete, global collapse due to fire all occurred on the same day and in the same place. There have been many raging building fires, much worse than existed in any of the WTC buildings, but no global collapse has ever resulted from those fires. Yet, the US government has told us that it was primarily fire that destroyed all three buildings at the WTC.
Photos and videos of the buildings show that the towers appeared to have exploded, starting at the top and then going all the way down. Also, high velocity bursts of debris shot out from ten to thirty floors below the collapse front.
At the top of each tower, the debris appeared to shoot upward and outward, as much of the solid structure turned to dust. This is counterintuitive to the idea that the building was being crushed downward. Large steel column assemblies were shot outward hundreds of feet, and some of them became embedded in surrounding buildings.
Many have asked: Is this what it looks like when a building is softened or weakened from fire? Independent investigators have done much work over the years to try and answer this question. In that time, peer-reviewed scientific articles have been published on various subjects related to the destruction of these buildings. One of those papers is called “Fourteen Points of Agreement with Official Government Reports on the WTC Destruction.”62 The points of agreement discussed therein lead to many problems that have yet to be explained.
One of the points of agreement is that all three buildings fell at near free-fall acceleration. A question NIST tried to answer was, “How could the WTC towers collapse in only 11 seconds (WTC 1) and 9 seconds (WTC 2), speeds that approximate that of a ball dropped from similar height in a vacuum (with no air resistance)?”
That is, one problem with the official story in this regard is that, if there were impact between an upper and lower section during the collapse, this would cause energy to be transferred and lost through deformations and structural breakage, which would slow the fall. But there was no deceleration, or slowing. The upper section, which appeared to be nothing but steel and dust, fell freely in each case.
We also agree that the fires in the buildings, whether driven by jet fuel or office furnishings, could not have melted the steel structure. NIST made the point that — “In no instance did NIST report that steel in the WTC towers melted due to the fires. The melting point of steel is about 1,500 degrees Celsius (2,800 degrees Fahrenheit). Normal building fires and hydrocarbon (e.g., jet fuel) fires generate temperatures up to about 1,100 degrees Celsius (2,000 degrees Fahrenheit). NIST reported maximum upper layer air temperatures of about 1,000 degrees Celsius (1,800 degrees Fahrenheit) in the WTC towers.”63
In other words, diffuse hydrocarbon fires such as these cannot produce temperatures high enough to melt steel. Unfortunately, many prominent media and political figures have suggested that very thing, and continue to do so.
It is also important to realize that the towers were designed for airliner impacts. John Skilling, the structural engineer in charge said that in the event of airliner impact — “the building structure would still be there.”64 We agree, so why did total collapse occur?
Each tower had 236 super-strength steel box columns making up the perimeter wall, and this was built around a core of 47 massive steel columns. The floor decking ran in a staggered arrangement between the core and the perimeter. To reduce the effects of fire, all of this steel structure was coated with a spray-applied fireproofing material before the buildings were occupied, and, in the aircraft impact zones, this fireproofing was upgraded in just the few years before 9/11.
Another point of agreement among all parties is that the theory that was claimed to be the most probable root cause for many years, called the pancake theory, is no longer supported by NIST.
The fire resistance of tall buildings like those at the WTC is ensured through testing of samples prior to construction. My former employer, Underwriters Laboratories (or UL), tested and certified the fireproofing used in the WTC towers, as seen in this quote from the company that manufactured the fireproofing.
“There is no reason for that product in a typical commercial environment to deteriorate,” because “[the] product had been thoroughly tested and approved by Underwriters Laboratories.”65
UL also tested the steel components used in the towers. This was well known because UL’s fire protection manager, Tom Chapin, said so in a letter he sent to the New York Times in 2002. Tom wrote: “The World Trade Center stood for almost an hour after withstanding conditions well beyond those experienced in any typical fire. In that time, thousands of people escaped with their lives. ASTM E-119 and UL’s testing procedures helped make that possible.”66
UL tested the steel components used in the WTC towers to meet the 1968 New York City fire code. The column assemblies had to withstand 3 hours of intense fire, and the floor assemblies had to withstand 2 hours of intense fire, in a test furnace. Loring Knoblauch, the CEO of UL when I worked there, confirmed that UL tested the WTC steel. He later wrote to me and a few others, saying:
- “We tested the steel with all the required fireproofing on, and it did beautifully.”
- “As we do not do follow-up service on this kind of product, we can give an opinion only on the test sample which was indeed properly coated.”
- “We test to the code requirements, and the steel clearly met those requirements and exceeded them.”67
UL later participated in the NIST WTC investigation, which was a clear conflict of interest.
The NIST WTC Report for the Twin Towers
The NIST WTC report is over 10,000 pages. It was originally published only for the Twin Towers. And like previous reports on the subject, it was focused only on the fire-induced collapse hypothesis. NIST made no real effort to examine the explosive demolition hypothesis.
The structure of the NIST report for the towers includes one summary report (NCSTAR 1) and eight sub-reports. This does not include the two sub-reports issued three years later for WTC building 7, which will be discussed in the second half of this paper.
NIST said its goals were to explain “why and how WTC buildings 1 and 2 collapsed after the initial impact of the aircraft” and “why and how WTC 7 collapsed.” The physical tests that NIST performed to reach its conclusions included tests to determine gas (i.e., air) temperatures and steel temperatures, and to investigate the possibility of floor failure and fireproofing loss.
Unfortunately for NIST, none of the tests it performed supported its conclusions. NIST therefore based its entire explanation on computer models. A summary of NIST’s collapse explanation is as follows:
- The aircraft severed columns
- Loads were redistributed
- Fireproofing was widely dislodged
- High temperatures weakened columns and floors
- Floors began to sag
- Sagging floors pulled exterior columns inward causing them to buckle
- Instability spread around entire building
- Finally, “global collapse ensued.”
The first step in NIST’s sequence was that the aircraft severed a number of columns. Again, it is agreed that the core columns were massive and over-designed and the perimeter columns were made of super-strong steel.
According to NIST, only a small percentage of columns were severed (14% in WTC1 and 15% in WTC2). However, the towers were originally designed such that one “could cut away all the first story columns on one side of the building, and partway from the corners of the perpendicular sides, and the building could still withstand design live loads and a 100 mph wind from any direction” (i.e. a tower could lose more than 25% of its columns without a problem).68
The second step in NIST’s sequence was that the gravitational load was redistributed among the remaining columns. NIST says loads on some columns were decreased (as much as 20%) and other loads were increased (up to 25%). But again, original design claims were that, “live loads on these [perimeter] columns can be increased more than 2,000% before failure occurs.”69
The third, very critical step in NIST’s sequence was that fireproofing was “widely dislodged.” NIST acknowledged that removal of fireproofing was critical to their collapse scenario:
“The towers would not have collapsed under the combined effects of aircraft impact and the subsequent multi-floor fires if the insulation had not been widely dislodged or had been only minimally dislodged by aircraft impact.”
Again, the steel structure was covered with a spray-applied fireproofing material. There were requirements for the fireproofing with regard to bond strength and those requirements were met.
The test that NIST performed to establish the critical fireproofing loss involved shooting 15 rounds from a shotgun at steel plates and bars coated with fireproofing. NIST’s final report included a 12-page appendix describing the shotgun test performed.70 It was not convincing. In fact, NIST did not explain how a Boeing 757 airliner could be converted into many thousands of shotgun blasts, which would need to be pointed in all directions in order to reach all of the steel surfaces.
Moreover, based on how much energy each shotgun blast would require, the energy requirements for this are too high. Previous calculations by engineers at MIT had shown that all the kinetic energy from the aircraft was consumed in breaking columns, crushing the floors and destroying the aircraft itself.71
NIST’s tests indicate that 1 MJ of energy was needed per square meter of surface area to shoot the fireproofing off. For the areas in question (more than 6,000 square meters of column, floor deck and floor joist surface) the extra energy needed would be several times greater than the entire amount of kinetic energy that NIST says was available to begin with (2,500 MJ).
The fourth step in NIST’s collapse initiation sequence requires large masses of steel columns and floors to be heated to temperatures that would make the steel soften. These temperatures do not support the NIST conclusions, but the physical tests that NIST performed resulted in even less agreement. The NIST report says that the gas (not steel) temperatures in the WTC towers were as high as 1000 °C. The highest steel temperatures referenced in the NIST report are 760 °C, which were produced by a computer model.
The physical tests NIST performed indicated that the steel saved for this purpose reached very low temperatures. NIST’s stated goal for this test was to “estimate the maximum temperature reached by available steel.”72 NIST accomplished this by selecting steel samples from an “enormous amount” of steel, and by emphasizing “regions of impact and fire damage” in the selection process.73
The tests performed by NIST to determine steel temperatures were:
- A paint deformation test — The result showed that only 3 out of 170 WTC samples had reached a temperature of 250 °C.
- A test of steel microstructure — This test demonstrated that none of the WTC steel samples had reached a temperature of 600 °C.
These results did not support NIST’s hoped-for conclusions — that the steel in the WTC towers had been softened or weakened from the fires.
Another point of agreement between NIST and independent scientists is that the fires in any given area were of short duration. NIST made it clear, as other scientists had observed, that “the initial jet fuel fires themselves lasted at most a few minutes,” and “at any given location, the duration of [air, not steel] temperatures near 1,000 °C was about 15 min to 20 min. The rest of the time, the calculated temperatures were near 500 °C or below.”74
NIST also claimed that the fires migrated around the core of each building over a period of time. For the north tower, this migration time lasted one full hour, according to NIST, before the fire reached the south wall where the collapse initiation occurred. This left less than 45 minutes of fire time at the south wall, where the fires would have migrated toward each other.
NIST claimed that the south wall bowed inward from the fires there, but the east and west walls, which had seen as much fire time, apparently showed no signs of bowing. Perhaps something else was happening at the south wall.
The fifth step in NIST’s sequence was that floors began to sag. My former company, UL, participated in the NIST investigation by conducting tests on models of WTC floor assemblies to examine the floor response to fire. The result was that only very slight sagging occurred in the tests, and no collapse occurred. After 45 minutes in a high temperature furnace, all four test models sagged only about 3 inches in the middle, and the major joist portions did not sag at all.
NIST deceptively transferred this data into its computer models, which somehow suggested dramatic 42-inch sagging, with joists bending downward severely.
To reiterate, UL and NIST built and tested exact replicas of WTC floor assemblies. A photo of one of those floor assemblies after the test can be found in the NIST report.75 This floor assembly was tested for fire resistance according to the standard method ASTM E-119. During this test, it was held in a furnace at a temperature of over 1000 °C for a period of two hours. The effects of the fire can be seen clearly — the mid-sections of the assembly sagged a few inches but the frame was not damaged, and the floor held its load without failure. The weight loaded onto the floor models tested was double what was known to have existed at the WTC. These experiments were performed by NIST and UL on 4 separate floor models, all of which had less fireproofing than the WTC floors were known to have on September 11.
NIST next contends that the sagging floors caused pull-in forces on exterior columns, causing them to fail. The first obvious problem with this is that sagging floors do not weigh more than non-sagging floors.
Moreover, to defeat the original design claims mentioned earlier, over 30 perimeter columns would have to be pulled in to cause a problem with structural stability. The floor assemblies formed an intense, staggered grid with the columns, however, and the force required to pull a perimeter column inward, and overcome that grid, was far greater than what a sagging floor assembly could provide.
The fact is that, even within NIST’s computer models, the sagging and pulling effects that NIST’s explanation depends on were not seen — not even for the most severe cases examined. Several quotes from the NIST report make that fact clear:
- sagging of floors in such a wide range over fire floors was not predicted by the full floor model analyses
- locations and magnitudes of pull-in forces were not accurately simulated
- pull-in forces were applied in some locations where the full floor analyses did not predict the development of such behavior76
NIST was simply not able to demonstrate this critical pull-in effect. Physical tests were not done, although that would have been decisive. The computer models did not indicate the forces were present either.
As a result, NIST made some fraudulent changes to the model. All the fireproofing was stripped off a large section of the computer modeled building, and exaggerated temperatures were applied for twice as long as NIST had said occurred in the failure zones. That is, NIST applied the exaggerated temperatures for 90 minutes instead of 45 minutes.
But even then the pull-in forces were not created in the computer, so NIST did something completely paradoxical. It disconnected the floors from the exterior columns, and then applied an imaginary pull-in force.77
This is the opposite of science.
The final step of NIST’s sequence was that the instability, caused by perimeter columns pulling inward, spread around the entire perimeter of the building. That claim was necessary to explain the perfectly uniform fall.
No tests of any kind were performed to confirm this instability spread. And for several reasons, it does not appear to be realistic as structural engineers have stated in the past that: “A steel structure, generally speaking, does not collapse suddenly when attacked by fire. There are unmistakable warning signs, namely, large deformations. TTT”78
Table 3-1 below reviews some of the key tests that NIST did perform, and how the results were used.
Table 3-1: NIST test results vs. NIST computer
|What were WTC steel temperatures?
|Up to 250 C
|Up to 760 C
|Fireproofing widely dislodged?
|Unrealistic shotgun test
|Fireproofing entirely removed
|How much could the floors have sagged ?
|3 inches after
2 hours of fire
|42 inches after
< 1 hour of fire
|Pull-in forces created?
|Floors disconnected and then imaginary forces were applied
|What were the actual “collapse” dynamics?
|No tests done
NIST has refused to share its computer models with the public. Therefore, the results cannot be independently verified.
NIST did not complete its objective because it did not tell us how the WTC towers collapsed. NIST simply proposed a collapse initiation sequence that is not supported by the evidence or the test results generated within the investigation.
But what evidence did NIST ignore when it ignored the actual collapse dynamics? The following questions are among those that remain unanswered.
What about resistance of structure below? If each floor each caused hesitation of only half a second, an extra 40 seconds would be needed. What about the observed “squibs”? What about the molten metal observed pouring from the building and the pools of molten metal in the rubble of both Towers and WTC 7? What about the intergranular melting and sulfidation found on the steel by the earlier FEMA investigation?
Ultimately, the NIST report for the WTC towers is false because NIST did not explain why and how the buildings collapsed, and the investigation was deceptive and unscientific. Additionally, NIST reported findings that were in direct contradiction to the physical testing performed and NIST omitted or distorted many important facts.
The NIST Report for WTC Building 7
NIST also issued a report on WTC 7, the third building that completely collapsed on 9/11. Although we should look closely at the final NIST explanation for this collapse, it is also informative to recognize that the previous government investigation, reported by FEMA in 2002, provided a best hypothesis that all agreed had only “a low probability of occurrence.”
WTC building 7 was 47 stories tall, was not hit by a plane and yet, at 5:20 in the afternoon on 9/11, it fell vertically and symmetrically to the ground, in 6.5 seconds.
After seven years of waiting, NIST finally put out its official report on building 7 in 2008. No one could have predicted the sequence of events that NIST says led to this building falling.
It says that normal office fires caused fully fireproofed steel beams to fail in one area of the building, and this failure led to the entire structure falling as it did, into a neat rubble pile. To reiterate, the official story of the “collapse” of WTC 7 is that a typical office fire caused this 47-story building to completely destroy itself in a matter of seconds. If we were to accept the NIST WTC7 report, we would have to conclude that no tall buildings are safe from the possibility of total unexpected collapse due to office fires.
All parties have agreed from the start that the collapse of WTC 7 was very problematic. Here are some quotes from the NIST and FEMA reports that make this clear.
“The performance of WTC 7 is of significant interest because it appears the collapse was due primarily to fire, rather than any impact damage from the collapsing towers.” — FEMA BPAT report on WTC 7
“This was the first known instance of the total collapse of a tall building primarily due to fires.” — NIST NCSTAR 1A, Executive Summary
The low probability hypothesis that FEMA described was that diesel fuel fires, driven by diesel fuel tanks located within the building, created intense fires that caused the collapse. For years, NIST promoted the diesel fuel fires hypothesis, but NIST abandoned that hypothesis in its final report.
“Diesel fuel fires did not play a role in the collapse of WTC 7.” — NIST final report on WTC 7
NIST also suggested for years that the damage caused by falling debris from the north tower was a root cause of the collapse of building 7. Ultimately, NIST gave up on that hypothesis as well.
“Other than initiating the fires in WTC 7, the damage from the debris from WTC 1 had little effect on initiating the collapse of WTC 7.” — NIST final report on WTC 7
And contrary to some media reports, the building design was not an issue either.
“Neither did the Con-Edison substation play a significant role in the collapse of WTC7.” — NIST final report on WTC 7
One serious problem that impaired the investigation was that most of the steel evidence was destroyed. The US House Committee on Science reported, in March 2002:
“In the month that lapsed between the terrorist attacks and the deployment of the [FEMA] BPAT team, a significant amount of steel debris…was removed from the rubble pile, cut into smaller sections, and either melted at the recycling plant or shipped out of the U.S. Some of the critical pieces of steel…were gone before the first BPAT team member ever reached the site.”
Of course, this destruction of evidence was a violation of the U.S national standard for fire and explosive investigations (NFPA 921), which says “it is essential to prevent the destruction or removal of evidence.”
Another serious problem was that NIST was clearly stumped for the first four or five years of the investigation, but then suddenly concluded that the answers were obvious. In 2006, NIST’s lead investigator, Shyam Sunder, said “But truthfully, I don’t really know. We’ve had trouble getting a handle on building No. 7.”79 Yet in 2008, when the final NIST report for WTC 7 was being issued, Sunder claimed that “the reason for the collapse of World Trade Center 7 is no longer a mystery” and “The public should really recognize the science is really behind what we have said…The obvious stares you in the face.”80
It is first important to note that NIST’s allegedly obvious explanation is entirely computer-based. NIST did no physical testing at all to support its building 7 report.
A summary of the NIST explanation for what happened to WTC 7 can be found in the NIST WTC 7 report. In this summary statement, NIST claims that:
“Fire induced expansion of the floor system surrounding column 79 led to the collapse of floor 13, which triggered a cascade of failures. In this case, the floor beams on the east side of the building expanded enough that they pushed the girder spanning between columns 79 and 44 to the west on floor 13. This movement was enough for the girder to walk off its support at column 79.”81
NIST says fires on the northeast corner of floor 12 heated the ceiling that included the floor beams for floor 13, causing thermal expansion of the beams which pushed the girder at column 79 off its seat. NIST says that column 79 buckled due to the loss of support from that girder, and then the whole building collapsed in a matter of seconds.
One fact that contradicts this scenario is the presence of shear studs on the floor beams and the girder in question. The NIST interim report from 2004 said that most of the beams and girders were made composite with the floor slabs using shear studs. In a deceptive turnabout, NIST did a reversal in its final report, saying that no shear studs were installed on any of the girders.
Unfortunately for NIST, it was not just its own 2004 interim report that contradicted this vital aspect of the final theory. The presence of shear studs on all the girders was also described by John Salvarinas, the project manager for building 7 from the company that supplied the steel components. A diagram from an academic paper that Salvarinas wrote in 1986 shows that there were 30 shear studs on that critical girder.82
NIST claims that thermal expansion caused the breakage of over one hundred high strength bolts. There were 28 shear studs on each of the affected floor beams, 30 shear studs on the critical girder, and 4 bolts at the column seat.
The mechanism that NIST claims caused all this damage is called differential thermal expansion, which happens when the expansion of the beam is much greater than the expansion of the concrete floor slab above it.
Thermal expansion is not a new phenomenon as NIST suggests, but has been a consideration throughout the history of structural design. That point was made by two building professionals from Australia who wrote a response to NIST on its building 7 report.83 These building professionals reported that they had actually done physical tests to see what thermal expansion would do to floor assemblies. These were just the kinds of tests that NIST should have done.
Because they had actually done the tests, the Australians were able to state that the shear studs would not fail because in a building fire, the floor slab would be heated as well and the entire composite assembly would expand together. So NIST’s final theory is at odds with actual experimental evidence from the testing of real floor assemblies.
Another problem with NIST’s theory is the distance that girder would have had to be pushed for it to walk off its seat, as NIST suggests. NIST reported that the girder seat at column 79 was 11 inches wide. Therefore the girder had to be pushed at least 5.5 inches, or half of that distance, to walk off the seat. That fact was made clear in statements made within the NIST report.
To repeat, NIST’s initial failure mechanism for WTC 7 was that the critical girder was pushed 5.5 inches by the floor beams. The 5.5 inches was needed in order for the vertical web of the girder, and therefore the center of mass of the girder, to move off of the seat.
Because thermal expansion is a function of temperature, we need to know what temperature NIST says the beams reached, so that we can estimate how much they expanded. This was a tricky question for NIST because at temperatures as high as 600 degrees Celsius the steel will lose strength and stiffness and therefore not be able to extend into the girder. At the same time, if the temperature is not high enough, there will not be enough expansion of the beams. What NIST settled on was the idea that the beam temperatures reached 400 degrees Celsius on the northeast corner of floor 12.
Related to this is another glaring problem in that NIST’s computer model had all the steel heating to extreme temperatures and all the bolts and other connections breaking within a matter of about 2 seconds. This is an example of how NIST’s computer modeling was not realistic.84
Once the temperature distribution needed for its theory was settled, NIST found a way to suggest that the differential thermal expansion could be possible, at least in the computer: NIST simply didn’t heat the floor slab in the computer model.85 Of course, differential thermal expansion cannot be measured if one of the materials you are trying to differentiate is not heated. One doesn’t have to be a scientist to understand that, but the approach is what most scientists would call fraud.
NIST’s theory has more problems than that. Given NIST’s temperature scenario, the amount of expansion by the beams would not satisfy the amount of expansion that NIST said was required, or 5.5 inches. NIST provided an example of the equation that scientists use to calculate thermal expansion.86 When we put the correct values into the equation, using 53-foot long floor beams and the temperature of 400 °C (to retain rigidity), we see that the maximum expansion would be only 3.3 inches.
As we already know from NIST, 3.3 inches would not be enough to cause the girder to walk off its seat. The girder would have had to be pushed at least 5.5 inches for NIST’s very improbable scenario to even begin. Therefore the basic premise of NIST’s explanation of failure for WTC 7 is not realistic.
NIST also said that there were seven-hour fires in building 7, which gave the impression that the fires were very long and very hot. NIST reported that “WTC 7 endured fires for almost seven hours,” and “Fires were ignited on at least 10 floors; however, only the fires on Floors 7 through 9 and 11 through 13 grew and lasted until the time of the building collapse.”
However, early photographs did not show fires on floors 11 through 13, where NIST says the first failures occurred, until after 2 pm. And the building fell less than 3.5 hours later. So there could not have been seven hour fires in the areas NIST reported as failing first.
Underwriters Laboratories provided the fire resistance information for WTC 7. This fact was stated clearly in the NIST report for building 7.87 NIST also reported that inspection of the fireproofing prior to 9/11 found that the fireproofing applied met the fire resistance requirements.88 The requirements were that these steel components had to withstand 2 to 3 hours of intense fire in standard tests.
An additional contradiction that NIST avoided was that its investigators knew that the fire load in the building would only support about 20 minutes of fire in a given area.89 When the NIST report talks about several hours of fire, it is deceptively referring to the time a fire lasts anywhere on a floor, not in one specific location on that floor. Underneath a specific floor beam, for example, the fire time is only about 20 minutes.
Another problem NIST did not explain is that the fires on floor 12 were completely burned out at least 30 minutes before the building fell.90 And it is well know that steel cools quickly after a source of heat is removed. We should be able to verify how long the fires lasted in a given location because there are photographs available from various times during the day. But it turns out that NIST did not use the photographs to verify its computer simulations.
A comparison of a photo in NIST’s report, taken at about 4 pm, and the NIST simulation of fires on floor 12 at the same time, shows no correlation between NIST’s simulation and what really happened. At approximately 4 o’clock, NIST’s computer simulation shows raging fires across the north side windows of floor 12. The photo from about the same time shows no fires in that area at all.91 NIST admits that “the observed fire activity gleaned from photos and videos was not a model input.”92 Again, this is not science and this is another example of why the NIST report is false.
There are significant problems with NIST’s description of the collapse dynamics as well. One problem is that the computer model output does not match what is seen in WTC7 collapse videos. Videos of the collapse show the building falling straight down with little deformation of exterior walls, whereas NIST’s computer model suggests the building crumpled from the sides before falling.93
Another problem is that NIST has admitted that building 7 fell at free-fall acceleration for a period of time, and that simply cannot occur without the structure below being removed by some unexplained forces.
Overall, with regard to WTC building 7, we can say with absolute certainty that the NIST report is unscientific and false for the following reasons.
- Physical tests performed by other experts disprove the NIST hypothesis
- The fire hypothesis is contradicted by the known fire resistance plan
- The fires in VTC 7 lasted only 20 minutes in each area while the steel components were rated for hours of fire resistance
- NIST’s final theory was based entirely on computer simulations that are not based on evidence
- NIST’s fire modeling contradicts the photographic evidence
- The fires in the critical areas (northeast corner of floor 12) were out long before collapse
- NIST did not heat the floor slabs in its model of differential thermal expansion
- NIST ignored known facts about shear studs on the critical girder
- The maximum thermal expansion possible could not have caused the girder to “walk off’ its seat
- The NIST computer result does not accurately model the collapse
Regardless of the fact that the NIST WTC 7 report is false in many ways, the scientific research community would like to see how NIST reached its conclusions. But as stated previously, NIST has refused to release its computer models to the public.
Structural engineer Ron Brookman made a Freedom of Information Act (FOIA) request to NIST in 2009 asking for the calculations and analysis behind the NIST claim of girder walk-off failures. NIST’s official response was that release of that information might jeopardize public safety.
Has NIST’s work on this subject been taken seriously with respect to building design and construction? The new, taller WTC 7 building was completed in 2006, at the time that NIST’s lead investigator said, “I don’t really know. We’ve had trouble getting a handle on building No. 7.”
Therefore the people who owned and constructed the new building 7 did not take NIST seriously, nor could they have done so due to the lengthy delays in production of NIST’s reports. Additionally, the NIST recommendations that have been adopted by the International Building Code council do not relate to the causes of destruction that NIST cited for the WTC towers and Building 7.
In conclusion, this essay has demonstrated the need for a new investigation into what happened at the WTC on 9/11. Official reports produced have not explained why and how the buildings collapsed, and the investigations were deceptive and unscientific. NIST reported findings that were in direct contradiction to the physical testing performed, and omitted or distorted many important facts. NIST claims that it cannot share the details of the computer models that support its findings with the public and therefore these cannot be independently verified as required in science. Finally, NIST’s explanations have not been taken seriously by the building construction community.
- Jones SE, Legge FM, Ryan KR, Szamboti AF, Gourley JR (2008b) Fourteen points of agreement with official government reports on the World Trade Center destruction, The Open Civil Eng J 2(1):35–40. doi:10.2174/1874149500802010035.
- See NIST WTC report NCSTAR 1, figure 6–36
- Seattle Times, February 27, 1993
- Quote from James Verhalen, chairman of the company that manufactured the fireproofing, United States Mineral Products, in the The New York Times, December 14, 2001.
- The New York Times, April 15, 2002.
- Personal email from Loring Knoblauch, CEO of UL, to Kevin Ryan, December 2003.
- Engineering News-Record, 1964.
- NIST WTC report NCSTAR 1-6A, Appendix C.
- Tomasz Wierzbicki et al, “Aircraft Impact Damage,” Massachusetts Institute of Technology.
- NIST Progress Report, May 2003.
- S. Sunder, W. Grosshandler, H. S. Lew, et al. “National Institute of Standards and Technology (NIST) federal building and fire safety investigation of the World Trade Center disaster, answers to frequently asked questions,” Gaithersburg, MD: National Institute of Standards and Technology, August 30, 2006. [Online]. Available: http://wtc.nist.gov.
- NIST WTC report NCSTAR 1-6B, figure 3-11.
- NIST WTC reports NCSTAR 1-6D and NCSTAR 1-6E.
- NIST WTC report NCSTAR 1-6, p115.
- Hart, Multi-Storey Buildings in Steel, Halsted Press.
- Shyam Sunder to New York Magazine, 2006.
- Shyam Sunder to Associated Press, 2008.
- NIST WTC report NCSTAR 1A, pages 21 to 22.
- John J. Salvarinas, Seven World Trade Center, New York, Fabrication and Construction Aspects, Canadian Structural Engineering 1 Conference, 1986.
- Letter from David Proe and Ian Thomas, professional research fellow and director respectively, Victoria University, to NIST during the public comment period, available at http://wtc.nist.gov.
- NIST WTC report NCSTAR 1-9, table 8-2.
- NIST WTC report NCSTAR 1-9, pp. 349 to 352.
- NIST WTC report NCSTAR 1-9, p 344.
- NIST WTC report NCSTAR 1A, p 7
- NIST WTC report NCSTAR 1A, p 7 (also see NCSTAR 1-9, table 8-1, p 340).
- See exchange between NIST advisor Charles Thornton and Shyam Sunder from the December 2007 advisory committee, http://wtc.nist.gov.
- See NIST’s 2004 interim report, figure L-24b.
- NIST WTC report NCSTAR 1-9, figures 3-6 and 5-136.
- NIST WTC report NCSTAR 1-9, p 378.
- NIST WTC report NCSTAR 1-9, figure 12-69.