Point WTC7-5: World Trade Center Building 7: NIST’s Analysis of the Collapse

Point WTC7-5: Initiation Is Not Valid

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In its reports on WTC 7, NIST (the National Institute of Standards and Technology) claimed that, for the first time in history, fire caused the complete collapse of a large, fire-protected, steel-framed building. In 2008, NIST published analyses purporting to show that fire-induced thermal expansion caused the collapse-initiation of the building.[1]

The reliability of the NIST analyses would obviously depend upon the inclusion of all structural features pertinent to the collapse-initiation. Information relevant to this issue came to light in late 2013.

The Official Account

NIST’s WTC 7 report shows that Girder A2001– which was in the northeast corner of the building, under the 13th floor and situated between Column 44 and Column 79 – was pushed off its seat at Column 79 by beams framing into it from the east due to thermal expansion of the beams caused by the raging fires produced by burning office materials.

This failure caused the large area supported by Girder A2001 to collapse down eight stories, to the 5th floor, leaving Column 79 laterally unsupported for nine stories, which caused it to buckle.

This single column failure then caused a complete north-to-south interior collapse, which in turn precipitated a complete east-to-west interior collapse, ultimately leaving the exterior columns laterally unsupported and causing all of them to buckle nearly simultaneously.

The Best Evidence

When NIST’s WTC 7 report was issued in November 2008, the structural drawings for the building were inexplicably missing. Accordingly, the report could not be scrutinized from a structural standpoint.

A Freedom of Information Act (FOIA) request was successful in obtaining the release of a large number of the drawings in late 2011.[2] Review of the released WTC 7 drawings showed that there were two serious structural feature omissions from the NIST analyses relevant to the NIST “collapse initiation” theory. They were:

1. Steel plate stiffeners that provided critical support for girder A2001.[3]

2. Floor beams S3007, G3007, and K3007, which provided lateral support for beam G3005.[4]

Analyses performed by independent engineers show that when the stiffeners and lateral support beams are included, NIST’s probable collapse sequence is impossible, because:

1. The girder flange for column 79 could not bend or fail with the stiffeners present.[5]

2. Beam G3005 – which NIST claimed buckled from thermal expansion and led to the collapse of WTC 7 – could not have buckled if G3005’s omitted lateral support floor beams S3007, G3007, and K3007 were present.[6]

In December 2013, well-known attorney William F. Pepper,[7] serving as legal counsel for Architects and Engineers for 9/11 Truth, sent a letter to the U.S. Commerce Department’s Inspector General, reporting these omissions. “It is the unanimous opinion of the structural engineers who have carefully studied this matter,” said Pepper, “that an independent engineering enquiry would swiftly reach the same conclusion.”[8]

Pepper added that his clients, after being ignored by NIST for nearly two years, finally got a response from a NIST public relations officer, who acknowledged that the stiffeners had been omitted. However, besides ignoring the omission of the lateral support beams, this PR officer said that the stiffeners did not need to be considered. Pepper said that his clients were in “disbelief and aghast” that NIST would omit these material features and, when the omissions were brought to NIST’s attention, completely dismissed their critical importance.


NIST’s claim that the collapse of WTC 7 was initiated when Girder A2001 was pushed off its seat at Column 79 is untenable.

With the alleged initiating event ruled out, all of NIST’s claims about subsequent structural failures must be considered baseless and invalid.

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References for Point WTC7-5

[1] “Structural Fire Response and Probable Collapse Sequence of World Trade Center Building 7. Volume 1. NIST NCSTAR 1-9,” 526-27.

[2] Mr. Ron Brookman obtained the drawings in late 2011. Mr. David Cole of the Nine Eleven Accountability Team discovered, in February 2012, that Frankel Fabrication Shop Drawing #9114 showed stiffeners providing support to a girder that had allegedly buckled. The full significance of the discovery of stiffeners that had been missing from the NIST report was first understood by mechanical engineer Tony Szamboti.

[3] The 2008 NIST report did not identify this girder as A2001, a designation that did not become available until two FOIA requests from Ron Brookman, FOIA #11-209 and 12-009, led to the release of Frankel drawing #E12/13 in November, 2011. This drawing is available in attorney William F. Pepper’s letter of December 12, 2013, to theU.S. Department of Commerce Inspector General: “The NIST Report On the Collapse of WTC Building 7 Challenged by 2,100 Architects and Engineers,” January 2014. It may also be downloaded in one of two zip files located in an article entitled “WTC 7 Blueprints Exposed Via FOIA Request: Building Plans Allow for Deeper Analysis of Skyscraper’s Destruction.”

[4]The NIST Report On the Collapse of WTC Building 7 Challenged by 2,100 Architects and Engineers,” January 2014.

[5] Ibid., Figure 11, p. 11.

[6] Ibid., Figures 12-16, pp. 12-14.

[7] William F. Pepper, whose primary work is international commercial law, is a barrister in the United Kingdom and admitted to the bar in numerous jurisdictions in the United States. He has represented governments in the Middle East, Africa, South America, and Asia. Pepper, who had been a friend of Martin Luther King, Jr., represented the King family in a wrongful death civil trial, which the family won. He is heavily involved in Human Rights Law, for a time convening the International Human Rights Seminar at Oxford University.

[8] William F. Pepper, “The NIST Report on the Collapse of WTC Building 7 Challenged by 2,100 Architects and Engineers,Journal of 9/11 Studies, January 2014.


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