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06 September 2008

Burn!, Gillo Pontecorvo, 1971, with Marlon Brando

Click the link to see the film, which is one of Brando's best.

Reflections in a Golden Eye, Directed by John Huston with Marlon Brando and Liz Taylor, from the novel by Carson McCullers

NIST WTC 7 Investigation Finds Building Fires Caused Collapse

August 21, 2008

Related Documents

(301) 975-3097

Michael Newman , NIST
(301) 975-3025

link to WTC 7 video page

GAITHERSBURG, Md.—The fall of the 47-story World Trade Center building 7 (WTC 7) in New York City late in the afternoon of Sept. 11, 2001, was primarily due to fires, the Commerce Department’s National Institute of Standards and Technology (NIST) announced today following an extensive, three-year scientific and technical building and fire safety investigation. This was the first known instance of fire causing the total collapse of a tall building, the agency stated as it released for public comment its WTC investigation report and 13 recommendations for improving building and fire safety.

“Our study found that the fires in WTC 7, which were uncontrolled but otherwise similar to fires experienced in other tall buildings, caused an extraordinary event,” said NIST WTC Lead Investigator Shyam Sunder. “Heating of floor beams and girders caused a critical support column to fail, initiating a fire-induced progressive collapse that brought the building down.”

photo of Shyam Sunder at news briefing

Shyam Sunder, NIST lead investigator, answers questions at a news briefing on August 21 about NIST's three-year study of the collapse of World Trade Center 7.

Photo by Don Berkemeyer
View hi-resolution image

“Video and photographic evidence combined with detailed computer simulations show that neither explosives nor fuel oil fires played a role in the collapse of WTC 7,” Sunder said. The NIST investigation team also determined that other elements of the building’s construction—namely trusses, girders and cantilever overhangs that were used to transfer loads from the building superstructure to the columns of the electric substation (over which WTC 7 was constructed) and foundation below—did not play a significant role in the collapse.

According to the report, a key factor leading to the eventual collapse of WTC 7 was thermal expansion of long-span floor systems at temperatures “hundreds of degrees below those typically considered in current practice for fire resistance ratings." WTC 7 used a structural system design in widespread use.

Citing its one new recommendation (the other 12 are reiterated from the previously completed investigation of the World Trade Center towers, WTC 1 and 2), the NIST investigation team said that “while the partial or total collapse of a tall building due to fires is a rare event, we strongly urge building owners, operators and designers to evaluate buildings to ensure the adequate fire performance of the structural system. Of particular concern are the effects of thermal expansion in buildings with one or more of the following features: long-span floor systems, connections not designed for thermal effects, asymmetric floor framing and/or composite floor systems.” Engineers, the team said, should be able to design cost-effective fixes to address any areas of concern identified by such evaluations.

The investigators also reported that if the city water main had not been cut by the collapse of World Trade Center towers 1 and 2 (WTC 1 and WTC 2), operating sprinklers in WTC 7 would likely have prevented its collapse. “Nevertheless,” Sunder said, “we recommend that building standards and codes be strengthened beyond their current intent to achieve life safety by preventing structural collapse even during severe fires like this one, when sprinklers do not function, do not exist or are overwhelmed by fire.”

Sunder identified several existing, emerging or even anticipated capabilities that could have helped prevent WTC 7’s collapse. He cautioned that the degree to which these capabilities improve performance remains to be evaluated. Possible options for developing cost-effective fixes include:

  • More robust connections and framing systems to better resist effects of thermal expansion on the structural system.

  • Structural systems expressly designed to prevent progressive collapse, which is the spread of local damage from a single initiating event, from element to element, eventually resulting in the collapse of an entire structure or a disproportionately large part of it. Current model building codes do not require that buildings be designed to resist progressive collapse.

  • Better thermal insulation (i.e., reduced conductivity and/or increased thickness) to limit heating of structural steel and to minimize both thermal expansion and weakening effects. Insulation has been used to protect steel strength, but it could be used to maintain a lower temperature in the steel framing to limit thermal expansion.

  • Improved compartmentation in tenant areas to limit the spread of fires.

  • Thermally resistant window assemblies to limit breakage, reduce air supply and retard fire growth.

The 12 recommendations reiterated from the WTC towers investigation address several areas, including specific improvements to building standards, codes and practices; changes to, or the establishment of, evacuation and emergency response procedures; and research and other appropriate actions needed to help prevent future building failures.

Determining the probable collapse sequence for WTC 7, NIST found that the impact of debris from the collapse of WTC 1 ignited fires on at least 10 floors of WTC 7, and the fires burned out of control on six lower floors. The heat from these uncontrolled fires caused thermal expansion of the steel beams on the lower floors of the east side of WTC 7, damaging the floor framing on multiple floors. Eventually, a girder on Floor 13 lost its connection to a critical interior column that provided support for the long floor spans on the east side of the building. The displaced girder and other local fire-induced damage caused Floor 13 to collapse, beginning a cascade of floor failures down to the fifth floor. Many of these floors had already been at least partially weakened by the fires in the vicinity of the critical column. This collapse of floors left the critical column unsupported over nine stories.

“When this critical column buckled due to lack of floor supports, it was the first domino in the chain,” Sunder explained. “What followed in rapid succession was a progression of structural failures. Failure first occurred all the way to the roof line—involving all three interior columns on the most eastern side of the building. Then, progressing from east to west across WTC 7, all of the columns in the core of the building failed. Finally, the entire façade collapsed.”

drawing showing locations of columns of typical WTC 7 floor

Diagram 1—Typical WTC 7 floor showing locations of columns (numbered). The buckling of Column 79 was the initiating event that led to the collapse of WTC 7. The buckling resulted from fire-induced damage to floors around Column 79, failure of the girder between Columns 44 and 79, and cascading floor failures. [Download high-res version]

The investigation team considered the possibility of other factors playing a role in the collapse of WTC 7, including the possible use of explosives, fires fed by the fuel supply tanks in and under the building, and damage from the falling debris of WTC 1.

The team said that the smallest blast event capable of crippling the critical column would have produced a “sound level of 130 to 140 decibels at a distance of half a mile,” yet no noise this loud was reported by witnesses or recorded on videos.

As for fuel fires, the team found that they could not have been sustained long enough, could not have generated sufficient heat to fail a critical column, and/or would have produced “large amounts of visible smoke” from Floors 5 and 6, which was not observed.

Finally, the report notes that “while debris impact from the collapse of WTC 1 initiated fires in WTC 7, the resulting structural damage had little effect in causing the collapse of WTC 7.”

The investigation team found that the design of WTC 7 was generally consistent with the New York City building code in effect at the time. The estimated 4,000 occupants of WTC 7 on the morning of Sept. 11 were evacuated without any fatalities or serious injuries.

To reach the conclusions in its report, NIST complemented its in-house expertise with private-sector technical experts; accumulated an extensive collection of documents, photographs and videos related to the WTC events of 9/11; conducted first-person interviews of WTC 7 occupants and emergency responders; analyzed the evacuation and emergency response operations in and around WTC 7; and performed the most complex computer simulations ever conducted to model a building’s response behavior and determine its collapse sequence due to a combination of debris impact damage, fires and a progression of structural failures from local fire-induced damage to collapse initiation, and, ultimately, to global collapse.

NIST welcomes comments on the draft report and recommendations—available online at http://wtc.nist.gov—received by noon Eastern Daylight Time on Sept.15, 2008. Comments (instructions for submission are available at http://wtc.nist.gov) may be submitted via:

  • e-mail to wtc@nist.gov;
  • fax to (301) 869-6275; or
  • surface mail to WTC Technical Information Repository, Attn: Stephen Cauffman, NIST, 100 Bureau Dr., Stop 8611, Gaithersburg, Md. 20899-8610.

The NIST investigation of WTC 7 was conducted under the National Construction Safety Team (NCST) Act, as part of its overall building and fire safety investigation of the World Trade Center disaster. The act gives NIST the responsibility for conducting fact-finding investigations of building failures that resulted in substantial loss of life or that posed significant potential of substantial loss of life. NIST has no regulatory authority under the NCST Act.

As an agency of the U.S. Department of Commerce, NIST promotes U.S. innovation and industrial competitiveness by advancing measurement science, standards and technology in ways that enhance economic security and improve our quality of life.

Related Documents

05 September 2008

A Video Collage on Anarchism

Very well done; great introduction to a long tradition in political thought. It's not about breaking windows.

04 September 2008

Glenn Greenwald on the St. Paul Raids

My Two Cents on Sarah Palin

She should not even be in the running. This is akin to Clarence Thomas: I couldn't care less (and didn't at the time) that he was black. He sucked: a C rating by the ABA. Shouldn't have even been nominated, and the Anita Hill thing was a typically spineless Democratic gambit to find "another reason" not to approve of the choice, whether she was telling the truth or not. I can't stand Alito, Roberts, and Scalia, but they have brains and the right to be on the court, objectively speaking. Of course they are dangerous, but they're not unqualified, from a certain perspective. Thomas was and is; ditto Palin.

The GOP is very good at catching liberals in their own silly, narcissistic identity politics, and when they squirm, they show how spineless they are. All the Demz have been doing is touting how "historic" the Hillobama run has been. As if there has never been a female ruler in the history of the world. Margaret Thatcher was female (presumably). Good model? Condi Rice? She's black, too. Let's vote for her! Colin Powell held very high office. Not particularly beneficial to the nation or the world. You can't run on such idiocies, using them to energize potential voters and donors, and then complain when the other side does it, too. But if you can't run on the policies that poll after poll shows that the Great Unwashed Masses want -- if both parties are far to the right of the population, in other words -- you have to run on this kind of garbage.

The entire notion of ethnic/gender loyalties is idiotic, dangerous, and undemocratic in the extreme, and follows logically from an election in which "qualities" are important, not issues. And identity politics is what you'd expect in a consumerist society in which class cannot be taken seriously and in which advertising/PR rules. Buy this razor and women will love you. Use this goo on your face, and you'll never grow old -- and men will love you. This kind of psychological assault (which is what it is) on rationality and truth starts the moment we flick the tube on or open a magazine and continues throughout our lives. It accustoms people to doublethink and irrationality -- as if our species needed any encouragement in that direction! And this industry is run by the corporations that rule our lives and amass capital for themselves and their hired servants (aka, white-collar workers).

And rightwingers are worried about the effect of a few silly self-refuting French postmodernists on Truth!

Palin is a rightwing nutjob with nothing to offer. At least Obama can give a good speech and seems to be intelligent. No, he has no business being where he is, either, and I don't care what color he is. The increasing lack of experience in presidential candidates is purposeful, not incidental. As issues recede and image dominates, the lack of a record becomes more important: the larger the screen upon which to project one's wishes. McCain is struggling to maintain his image as a "maverick," which is totally belied by his record. But in a pseudoevent, that's all the matters (Boorstin's book The Image is worth reading -- prescient; nailed the nascent Camelot myth pretty good).

Whether any of us prefer one screen to another is, to me, kind of beside the point. You can't have a representative democracy based on demagoguery and leader-worship. As Aristotle and Plato warned, rightly.

Or, as Ben Franklin put it, when asked what he thought of the Constitution that had just been written:

I agree to this Constitution with all its faults, if they are such; because I think a general Government necessary for us, and there is no form of Government but what may be a blessing to the people if well administered, and believe farther that this is likely to be well administered for a course of years, and can only end in Despotism, as other forms have done before it, when the people shall become so corrupted as to need despotic Government, being incapable of any other.
"Need" may be challenged, but the universal historical tendency toward despotism is unquestionable, as is the validity of Franklin's prediction.

03 September 2008

Call to Action on Behalf of DN! Journalists Facing Charges for Reporting on the Republican National Convention

Today it is critical that you make your voice heard in the Ramsey County Attorney and St. Paul City Attorney offices. Demand that they drop all pending and current charges against journalists arrested while reporting on protests outside the Republican National Conventions.

The Ramsey County Attorney’s office is in the process of deciding whether or not to press felony P.C. (probable cause) riot charges against Democracy Now! Producers Sharif Abdel Kouddous and Nicole Salazar. Please contact Ramsey County Attorney Susan Gaertner by all means possible to demand that her office not press charges against Kouddous and Salazar.

Ramsey County Attorney Susan Gaertner
RCA at co.ramsey.mn.us (cc: dropthecharges at democracynow.org)

Susan Gaertner for Governor
info at susangaertner.com (cc: dropthecharges at democracynow.org)
(612) 978-8625

The St. Paul City Attorney’s office has already charged Amy Goodman with misdemeanor obstruction of a legal process and interference with a peace officer. Contact St. Paul City Attorney John Choi by all means possible to demand that the charges against Goodman be dropped immediately.

St. Paul City Attorney John Choi
john.choi at ci.stpaul.mn.us (cc: dropthecharges at democracynow.org) (651) 266-8710

Goodman was arrested while questioning police about the unlawful detention of Kouddous and Salazar who were arrested while they carried out their journalistic duties in covering street demonstrations at the Republican National Convention.

During the demonstration in which the Democracy Now! team was arrested, law enforcement officers used pepper spray, rubber bullets, concussion grenades and excessive force against protesters and journalists. Several dozen demonstrators were also arrested during this action, as was a photographer for the Associated Press.


Be sure to cc: dropthecharges@democracynow.org on all emails so that our team can deliver print outs of your messages to the St. Paul City Attorney and Ramsey County Attorney offices.


Amy Goodman Arrest

Nicole Salazar Arrest

Media coverage of RNC arrests


Free Press campaign


Free Press Petition to Release Journalists Arrested at RNC

Dear Doug,

Reports of journalists, bloggers and videomakers being arrested keep rolling in. The St. Paul police department's targeting of journalists, including Amy Goodman of Democracy Now! and the I-Witness videomakers, is having a chilling effect on free speech as the city hosts the Republican National Convention.

Many in the mainstream media are ignoring these attacks on journalism -- and some independent media makers are still in jail. But in less than 24 hours, more than 35,000 people have signed our letter demanding that press intimidation cease immediately and that all charges against journalists be dropped.

This is an incredible response. Help deliver the message that a free press will not be intimidated!

Help Us Reach 50,000 Letters: Take Action Now



P.S. Below is yesterday's e-mail with detailed information about the arrests.

Dear Friend,

Amy Goodman Arrested

Police in St. Paul arrested several journalists yesterday, including Democracy Now! host Amy Goodman.

Stand Up for Independent Journalism

Yesterday, police in St. Paul arrested several journalists, including Democracy Now! host Amy Goodman and an AP photographer as they were covering protests of the Republican National Convention.

Amy Goodman and others were released last night, but the story is not over.

We need you to cosign our public letter demanding that press intimidation cease immediately, and that all charges be dropped. It will be delivered immediately to St. Paul Mayor Chris Coleman, the RNC Host Committee and the local prosecuting attorneys. We need 10,000 signatures in the next 24 hours, so please take action now:

Sign the Letter: Drop All Charges Against Journalists

In addition to these arrests, police with firearms drawn raided a meeting of the video journalists' group I-Witness and arrested independent media, bloggers and videomakers. We’re also receiving late-breaking reports of other arrests.

By signing this letter, you’re sending a powerful message: Officials must rein in aggressive and violent tactics by local law enforcement, stop the targeting of journalists and immediately drop all charges against them.

Reporting by independent journalists is vital to a functioning democracy. Americans must have access to diverse sources of information to hold their leaders accountable. Journalists must be free to do their jobs without intimidation.

Please Take Action by Signing this Letter

Don’t wait. We need a free press now more than ever. Tell your friends and take action now!

Thank you,

Josh Silver
Executive Director
Free Press

1. Watch the video of Goodman's arrest.

2. See other journalists being arrested as reported by UpTake.

3. News of the AP arrest.

4. Learn more about the arrest of an ABC News producer during the Democratic Convention in Denver.

5. Watch the video of the police raid of I-Witness journalists (Caution: strong language).

Twin Cities Violence: Just What The RNC Ordered

Wanted Immediately: An Editor for our Election Protection Work on SourceWatch

Amy Goodman & Two Democracy Now! Producers Arrested at RNC Protest

More here:

Outside the convention Tuesday, police fired flash bang grenades and tear gas at peaceful protesters after the end of a march led by the Poor People’s Economic Human Rights Campaign. The grenades are designed to produce a deafening bang and a blinding flash. Twin Cities police arrested at least 10 people on Tuesday bringing the total number this week to over three hundred. Dozens of activists jailed on Monday were still being slowly released last night. Democracy Now caught up with a medic shortly after he was freed after more than twenty-hours behind bars.

Medic: “There are still a whole lot of people in jail waiting to get out and a lot of people are really uncertain about how they are getting out some of them have various injuries from pepper spray getting beat up by the cops before getting in there…just kind of uncertain what is going on.”

Meanwhile, the Ramsey County sheriff’s office has admitted it infiltrated and spied on a prominent protest group in the Twin Cities known as the RNC Welcoming Committee for the past year. Two informants and an undercover investigator posed as members of the group which the sheriff’s office deemed to be a “organized criminal enterprise.” The RNC Welcoming Committee describes itself as an anarchist/anti-authoritarian organizing body.

Vidal on Obama and the DNC