2nd House Hearing: Collapse of the World Trade Center, May 1, 2002

http://commdocs.house.gov/committees/science/hsy78961.000/hsy78961_0f.htm

Segment 1 Of 3     Next Hearing Segment(2)

SPEAKERS       CONTENTS       INSERTS

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THE INVESTIGATION OF THE WORLD TRADE CENTER COLLAPSE: FINDINGS, RECOMMENDATIONS, AND NEXT STEPS

HEARING

BEFORE THE

COMMITTEE ON SCIENCE

ONE HUNDRED SEVENTH CONGRESS

SECOND SESSION

MAY 1, 2002

Serial No. 107–61

Printed for the use of the Committee on Science

THE INVESTIGATION OF THE WORLD TRADE CENTER COLLAPSE: FINDINGS, RECOMMENDATIONS, AND NEXT STEPS

78–961PS
2002
THE INVESTIGATION OF THE
WORLD TRADE CENTER COLLAPSE: FINDINGS,

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RECOMMENDATIONS, AND NEXT STEPS

HEARING

BEFORE THE

COMMITTEE ON SCIENCE
HOUSE OF REPRESENTATIVES

ONE HUNDRED SEVENTH CONGRESS

SECOND SESSION

MAY 1, 2002

Serial No. 107–61

Printed for the use of the Committee on Science

Available via the World Wide Web: http://www.house.gov/science

COMMITTEE ON SCIENCE

HON. SHERWOOD L. BOEHLERT, New York, Chairman

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LAMAR S. SMITH, Texas
CONSTANCE A. MORELLA, Maryland
CHRISTOPHER SHAYS, Connecticut
CURT WELDON, Pennsylvania
DANA ROHRABACHER, California
JOE BARTON, Texas
KEN CALVERT, California
NICK SMITH, Michigan
ROSCOE G. BARTLETT, Maryland
VERNON J. EHLERS, Michigan
DAVE WELDON, Florida
GIL GUTKNECHT, Minnesota
CHRIS CANNON, Utah
GEORGE R. NETHERCUTT, JR., Washington
FRANK D. LUCAS, Oklahoma
GARY G. MILLER, California
JUDY BIGGERT, Illinois
WAYNE T. GILCHREST, Maryland
W. TODD AKIN, Missouri
TIMOTHY V. JOHNSON, Illinois
MIKE PENCE, Indiana
FELIX J. GRUCCI, JR., New York
MELISSA A. HART, Pennsylvania
J. RANDY FORBES, Virginia

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RALPH M. HALL, Texas
BART GORDON, Tennessee
JERRY F. COSTELLO, Illinois
JAMES A. BARCIA, Michigan
EDDIE BERNICE JOHNSON, Texas
LYNN C. WOOLSEY, California
LYNN N. RIVERS, Michigan
ZOE LOFGREN, California
SHEILA JACKSON LEE, Texas
BOB ETHERIDGE, North Carolina
NICK LAMPSON, Texas
JOHN B. LARSON, Connecticut
MARK UDALL, Colorado
DAVID WU, Oregon
ANTHONY D. WEINER, New York
BRIAN BAIRD, Washington
JOSEPH M. HOEFFEL, Pennsylvania
JOE BACA, California
JIM MATHESON, Utah
STEVE ISRAEL, New York
DENNIS MOORE, Kansas
MICHAEL M. HONDA, California

C O N T E N T S

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May 1, 2002
Witness List

Hearing Charter

Opening Statements

Statement by Representative Sherwood L. Boehlert, Chairman, Committee on Science, U.S. House of Representatives
Written Statement

Statement by Representative Ralph M. Hall, Minority Ranking Member, Committee on Science, U.S. House of Representatives
Written Statement

Statement by Representative Anthony Weiner, Member, Committee on Science, U.S. House of Representatives
Written Statement

Statement by Representative Constance Morella, Member, Committee on Science, U.S. House of Representatives
Written Statement

Statement by Representative Steve Israel, Member, Committee on Science, U.S. House of Representatives

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Statement by Representative Felix J. Grucci, Jr., Member, Committee on Science, U.S. House of Representatives
Written Statement

Prepared Statement by Representative Sheila Jackson Lee, Member, Committee on Science, U.S. House of Representatives

Panel

Mr. Robert F. Shea, Acting Administrator, Federal Insurance and Mitigation Administration, Federal Emergency Management Association
Oral Statement
Written Statement
Biography

Dr. W. Gene Corley, American Society of Civil Engineers, Chair of Building Performance Assessment Team reviewing the WTC disaster; accompanied by Dr. Jonathan Barnett, Professor, Center for Fire Safety Studies, Worcester Polytechnic Institute
Oral Statement
Written Statement
Biography
Financial Disclosure

Dr. Arden L. Bement, Jr., Director, National Institute of Standards and Technology

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Oral Statement
Written Statement
Summary of proposed NIST investigation plan
NIST/FEMA memorandum of understanding
Biography

Professor Glenn P. Corbett, Assistant Professor of Fire Sciences, John Jay College, New York City
Oral Statement
Written Statement
Biography
Financial Disclosure

Discussion
Evacuation/Emergency Response Procedures
Access to Investigation Materials
Stairwell Separation
Sprinkler System Redundancy
Egress Systems
Building Codes
WTC Building 7
Stairwell Materials
NIST Subpoena Power
Stairwell Separation/Water System Redundancy
Building Codes
NIST Funding Needs

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Witness Comments on the National Construction Safety Team Act
NIST Building Research Capabilities
NIST Funding of the Investigation
Fire and Building Failure
WTC Building 7
NIST Follow-up Investigation
Building Codes/Code-Related Research
NIST Subpoena Power
Building Performance Information Repository

Appendix 1: Additional Material for the Record

Letter to Chairman Sherwood Boehlert from Mark D. Wallace, Deputy General Counsel, Federal Emergency Management Agency
Letter to Dr. Arden L. Bement, Jr., from Francis J. Lombardi, P.E., Chief Engineer, Port Authority of New York and New Jersey
Statement of the International Code Council
World Trade Center Building Performance Study: Data Collection, Preliminary Observations, and Recommendations, FEMA 403/May 2002

THE INVESTIGATION OF THE WORLD TRADE CENTER COLLAPSE: FINDINGS, RECOMMENDATIONS, AND NEXT STEPS

WEDNESDAY, MAY 1, 2002

House of Representatives,

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Committee on Science,

Washington, DC.

The Committee met, pursuant to call, at 12:11 p.m., in Room 2318 of the Rayburn House Office Building, Hon. Sherwood L. Boehlert (Chairman of the Committee) presiding.

78961a.eps

HEARING CHARTER

COMMITTEE ON SCIENCE

U.S. HOUSE OF REPRESENTATIVES

The Investigation of the

World Trade Center Collapse:

Findings, Recommendations, and Next Steps

WEDNESDAY, MAY 1, 2002

12:00 P.M.–3:00 P.M.

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1. Purpose

On Wednesday, May 1, at noon the House Committee on Science will hold a hearing on the key findings and recommendations of the Federal Emergency Management Agency’s (FEMA) investigation into the collapse of the World Trade Center (WTC). The hearing will also review the plans of the National Institute of Standards and Technology (NIST) to conduct a more extensive follow-up investigation and to establish a comprehensive research and development plan to improve standards, practices and codes for buildings and fire. In addition, the witnesses will be asked to comment on a bill to give NIST additional investigative powers.

The hearing will address the following overarching questions:

1. What are the findings and recommendations of the report of FEMA’s building performance assessment team (BPAT) regarding the collapse of the World Trade Center?

2. What are NIST’s plans to follow up on the recommendations of the BPAT report?

3. How should NIST be involved in investigating catastrophic building failures in the future?

4. To what extent does NIST require new authorities, such as the ability to issue subpoenas, in order to conduct investigations of building failures?

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2. Issues

Since the March 6, 2002 Science Committee hearing on the collapse of the World Trade Center, FEMA has readied its report of the Trade Center disaster for release, NIST has prepared initial plans for taking the reins from FEMA to conduct its own, more extensive investigation, and the Administration has requested supplemental funding of $16 million to pay for NIST’s investigation. At the same time, a number of new issues have arisen:

It is unclear how NIST’s $16 million follow-up investigation will differ from that of the BPAT’s. While NIST has made clear the goals for its proposed follow-up investigation to collect more data on the World Trade Center disaster and has outlined the general issues it plans to probe, many aspects of the investigation remain undefined. For example, it is still unclear how much data remains to be collected or what kind of data is needed to determine whether changes in building codes are necessary.

It is uncertain whether NIST will receive the funding necessary to pay for its planned investigation. The Administration’s request of $16 million for further investigation of the World Trade Center disaster was made on behalf of FEMA rather than NIST. While FEMA has stated that NIST is in charge of the follow up investigation and is willing to transfer this funding to NIST, it is unclear whether it has the authority to do so. FEMA has promised to have a determination from its Office of General Counsel at the time of the hearing as to whether additional authority from Congress would be required to transfer the funds to NIST.

It is unclear whether the second phase of NIST’s follow-up plans—a 3-year research effort to determine whether and how changes in building codes should be made—will receive the commitment for funding it requires. In addition to conducting a $16 million follow-up investigation to collect more data regarding the Trade Center disaster, NIST also proposes to conduct longer-term research on issues identified by the BPAT report. For example, NIST plans to develop computer models of the collapse and conduct experiments to better understand the effect of fire on steel connections in buildings. So far, the Administration has requested $2 million in the FY03 budget for this type of research and NIST has committed an additional $2 million next year from amounts that otherwise would go to its building and fire laboratory, the principal lab that will do the research in any case. NIST estimates, however, that the total cost of the program will be approximately $40 million over the next three years. While NIST has said that some funds may be contributed by private sources, it is unclear if any such commitments have been made. If adequate funding for NIST’s research efforts are not secured it is unclear how NIST will use the information it collects in its investigation to improve standards, practices and codes for buildings and fire.

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It is unclear what role NIST will play in investigating future building failures. FEMA received heavy criticism at the last Science Committee hearing for shortcomings in the way in which it conducted the investigation of the collapse of the World Trade Center. Following the hearing, FEMA entered into a memorandum of understanding (MOU) with NIST to enlist NIST’s support in future investigations. The details of that MOU have not yet been worked out, and it is unclear what kinds of building collapses, if any, will lead FEMA to ask for NIST’s assistance in the future.

NIST may require additional authorities to carry out an effective building investigation. FEMA’s investigation into the World Trade Center collapse was inhibited at several turns by an inability to access the disaster site quickly, preserve evidence, and obtain necessary documentary evidence, such as blueprints, in a timely way. Several observers, including the families of the Trade Center victims, have called for World Trade Center investigators to be granted authorities akin to those of the National Transportation Safety Board (NTSB), which is authorized by statute to enter the site of airplane crashes, preserve evidence, and issue subpoenas to witnesses or for documents to facilitate its investigation.

3. Background

On September 11, 2001, terrorists crashed two fuel-laden commercial Boeing 767 airplanes into the north and south towers of the World Trade Center complex in New York City. Although each building withstood the initial impact, both suffered complete collapse within two hours. While more than 25,000 people were successfully evacuated from the towers, nearly 3,000 building occupants and emergency responders died when the buildings fell.

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FEMA responded to this disaster by deploying a building performance assessment team (BPAT)—a group of experts in engineering, design, construction, and building codes—to conduct a formal analysis of the causes of the collapse of the buildings and determine what can be learned from the disaster to save lives in the future. Concerns regarding the timing of the BPAT deployment, their access to the site and building records, premature disposal of evidence, and FEMA’s lack of regular communication with the public were the subject of a previous Science Committee hearing, and are explained in detail in Appendix 1 (the March 6 hearing charter).

FEMA and the American Society of Civil Engineers (ASCE), the organization heading up the WTC BPAT, will announce the results and recommendations of the BPAT report at the hearing. Preliminary drafts of the report reveal that despite the massive impacts that punctured the building’s exterior frame of support, the buildings were able to successfully redistribute the weight from higher floors and remain standing. However, the fires in the buildings, fed by jet fuel and flammable building contents, proved too intense, producing at their peak an amount of energy equivalent to the output of a typical nuclear power plant. The fires caused the steel, stripped of its fireproofing by the impact of the planes, to weaken and buckle. With water pipes for fire suppression systems severed, the fires led to the eventual progressive collapse of the buildings.

The report highlights potential reasons for why the two towers, almost identical in design, performed differently under the stresses of the disaster. It also identifies critical features that enabled so many to evacuate, and the design elements that may have played a role in the collapse and prevented people above the impacts from being able to exit the buildings. (See a March 29th article from The New York Times, which is attached as Appendix 2, for further discussion of the BPAT’s findings and recommendations.)

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The report also calls for further study of several issues that were beyond the scope of the BPAT investigation. For example, the report recommends developing methods to predict performance of building materials in fires, improving existing models of how fires spread, analyzing the WTC evacuation and proposing improvements to evacuation procedures for tall buildings, involving engineers in the processes that emergency personnel use to develop plans for hazard assessment, etc. The report also outlines specific needs for further investigation into the performance strengths and weaknesses of each building within the WTC complex.

NIST Investigation and Research Program

NIST’s Building and Fire Research Laboratory (BFRL) carries out research in fire science, fire safety engineering, and structural, mechanical, and environmental engineering. It is the only federal laboratory dedicated to research on building design and fire safety.

In January, FEMA asked NIST to take over the next phase of the investigation of the collapse essentially to build upon the BPAT recommendations and conduct a more thorough investigation of the events leading to the collapse. While waiting for the BPAT report to be released, NIST has developed a two-part strategy: investigation and long-term research.

First, NIST will conduct a $16 million comprehensive and thorough two-year investigation to determine, through a technical analysis, why and how WTC 1, 2 and 7 collapsed. The investigation will cover subjects including evacuation, standards that were used in the construction and maintenance of the buildings, and whether new technologies for future buildings could reduce the risk of collapse. For example, the fire-performance of steel trusses and connectors with spray-applied fireproofing is not well understood, but may have been critical to the ultimate failure of the Trade Center. NIST will purchase floor trusses similar to those in the WTC 1 & 2, spray on fireproofing as it was done in the buildings, and subject them to fire and mechanical conditions (vibrations and impacts) like those experienced on September 11. Information from these tests not only can answer questions about the exact nature of the collapse of the buildings, but also will serve as the foundation for developing performance-based criteria for fireproofing steel, which is a part of NIST’s long-term research agenda.

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While the first part of the strategy specifically focuses on investigating the collapse of the World Trade Center buildings 1, 2, and 7, NIST believes that many of the ”lessons learned” through a technical investigation can have broad applicability to building design. NIST is developing a public-private research plan to focus on many of the long-term research needs that the BPAT report recommended. NIST estimates that this program could cost approximately $40 million over the next three years. The Administration has already requested $2 million in the FY03 budget and NIST has committed another $2 million by shifting funding in the BFRL’s base funding level to this purpose. The public-private program will address four national needs:

To develop a better understanding the response of structures and materials to fire, and options for improving the safety of existing buildings;

To develop a better understanding human behavior in emergency evacuations, including exploring technologies to assist mobility-impaired people, and to develop standards for the equipment that fire and emergency responders use;

To reduce the vulnerability of buildings to chemical, biological, and radiological attacks; and

To develop a roadmap for changes to building codes, standards and designs, and for disseminating research to industry.

Calls for New Authorities for NIST

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While NIST is optimistic that the investigation combined with the research plan can ultimately lead to changes in building codes, standards and practices, as well as improvements in emergency response and evacuation procedures, some NIST officials agree with families of Trade Center victims that NIST needs new authorities in order to conduct an effective investigation. They believe that, like the National Transportation Safety Board, NIST should have the authority to issue subpoenas to obtain critical documents or persuade unwilling witnesses to provide information important to the investigation. Proponents of granting NIST subpoena power point to the fact that the BPAT team had requested but were denied several kinds of documentary evidence to assist its investigation, such as the recordings of emergency responders and 911 calls made that could help investigators determine what was happening inside the World Trade Center buildings before they collapsed on September 11.

4. Witnesses

The following witnesses will address the Committee:

Mr. Robert Shea, Acting Administrator, Federal Insurance and Mitigation Administration, Federal Emergency Management Agency

Dr. W. Gene Corley, P.E., S.E., American Society of Civil Engineers, Chair of Building Performance Assessment Team reviewing the World Trade Center disaster

Dr. Arden Bement, Director, National Institute of Standards and Technology

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Professor Glenn Corbett, Assistant Professor of Fire Science at John Jay College, New York City

5. Questions

The witnesses were asked to address the following issues before the Committee:

Mr. Shea:

Instead of formally testifying before the Committee, Mr. Shea will officially release the results of the BPAT study of the World Trade Center disaster and remain on the panel to respond to questions.

Dr. Corley:

Dr. Corley was asked to describe the key findings and recommendations of the World Trade Center Building Performance Study. His focus is to be on any ”lessons learned” from the collapse, any recommendations to alter building codes, standards or practices, and any recommendations to which the National Institute of Standards and Technology, in its follow-up investigation and study, should be especially attentive.

The Committee posed the following questions for Dr. Corley to address in his written testimony:

What areas critically need further study but lie outside the scope of your report?

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What additional data collecting and modeling must be done in order to derive ”lesson learned” from this disaster and who should do this work?

What barriers stand in the way of having the recommendations of the BPAT adopted in the building codes community and how can these barriers be overcome?

What work, if any, does ASCE plan to conduct, as follow-up to this study, to develop any changes to building practices, standards and codes?

Dr. Bement:

Dr. Bement was asked to describe the $16 million investigation that NIST proposes to conduct into the World Trade Center disaster, with particular attention to the following: How will the investigation differ from, and follow up on the Federal Emergency Management Agency’s BPAT study of the WTC disaster?

The Committee also requested that he describe NIST’s proposal to follow the investigation with additional research, with particular attention to:

How will NIST’s proposed research program differ from the investigation?

How will the research effort or the investigation lead to changes in building standards, practices and codes?

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What additional authorities, if any, will NIST need in order to conduct a complete and through investigation?

What specific steps is NIST taking to ensure that NIST communicates its plans to the public and professional communities?

Professor Corbett:

Professor Corbett was asked to evaluate the NIST’s proposed study with particular attention to the following questions:

Based on your current understanding of the areas that NIST plans to cover in its proposed investigation and follow-up research plan, how should NIST ensure that all of the areas (especially ones outside of the Agency’s traditional expertise) are adequately addressed in its plan?

How should NIST implement its investigation to ensure that its conclusions are definitive, defensible, and most useful in helping to improve building codes, fire safety standards, etc?

What additional authorities, if any, do you think NIST must have in order to conduct a thorough and effective investigation, and why?

6. Appendices

Appendix 1:

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Hearing charter: ”Learning from 9/11: Understanding the Collapse of the World Trade Center,” Committee on Science, U.S. House of Representatives, March 6, 2002.

Appendix 2:

The New York Times article from March 29, 2002: ”Towers Withstood Impact, But Fell to Fire, Report Says” by James Glanz and Eric Lipton. p. A1.

Appendix 1

HEARING CHARTER

COMMITTEE ON SCIENCE

U.S. HOUSE OF REPRESENTATIVES

Learning from 9/11—Understanding

the Collapse of the World Trade Center

WEDNESDAY, MARCH 6, 2002

12:00 P.M.–2:00 P.M.

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2318 RAYBURN HOUSE OFFICE BUILDING

I. Purpose

On Wednesday, March 6, at noon the House Committee on Science will hold a hearing on the investigation into the collapse of the World Trade Center (WTC). Witnesses from industry, academia, and government will testify on the catastrophic collapse of the WTC complex and subsequent efforts by federal agencies and independent researchers to understand how the building structures failed and why. By scrutinizing the steel and other debris, blueprints and other documents, and recorded images of the disaster, engineers, designers, and construction professionals may learn valuable lessons that could save thousands of lives in the event of future catastrophes, natural or otherwise.

The Committee plans to explore several overarching questions raised by the collapse and the ensuing investigation:

1. What have we learned about how the Federal Government investigates catastrophic building collapses, and are any changes warranted?

2. What have we learned about the collapse of the World Trade Center, including which structural elements failed first, and why?

3. How will we know what changes, if any, are warranted in building and fire codes as a result of lessons learned from the World Trade Center’s collapse?

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4. Has the World Trade Center disaster exposed any gaps in our understanding of buildings and fire, and are changes needed in the Federal Government’s research agenda?

2. Background

At 8:47 a.m. on the morning of September 11, 2001, terrorists crashed a fuel-laden Boeing 767 into the north tower (Tower 1) of the World Trade Center (WTC) complex. Approximately 16 minutes later, a second Boeing 767 slammed into the south tower (Tower 2), exploding upon impact and engulfing several of the building’s upper floors in flames. While the performance of both towers exceeded their design specifications—the buildings were designed to withstand the force from the initial impact of a 707 jet—the subsequent structural and fire damage still caused the buildings to fall. Tower 2 collapsed in less than an hour, killing victims trapped above the flames and rescue workers in and around the building. Thirty minutes later, Tower 1 met the same fate. While more than 25,000 people were successfully evacuated from the towers, nearly 3,000 people and emergency responders were killed in the collapses. As the day progressed, the remaining WTC buildings collapsed as well, including Building 7, which burned for 8 hours before crumbling to the ground. Fortunately, the later building collapses produced no casualties.

In the wake of the collapses, search and rescue workers launched an around-the-clock recovery effort to find and recover survivors and victims who perished. To make way, literally tons of twisted steel and fractured concrete were removed from the rubble pile and loaded onto convoys of bulldozers and flatbed trucks to be carried away to recycling plants and landfills.

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Researchers also began to respond immediately. Among the first were National Science Foundation (NSF)-funded social scientists and engineers who arrived at the WTC site within 48 to 72 hours after the tragedy to begin collecting data. Similarly, the American Society of Civil Engineers (ASCE) formed a Disaster Response Team within hours of the first plane strike. On September 12th, the Federal Emergency Management Agency (FEMA) and its contractor, Greenhorne and O’Mara, Inc., located in Greenbelt, Maryland, commenced the development of a Building Performance Assessment Team (BPAT; explained more fully on the next page) to conduct a formal analysis of the progressive collapses and produce a report of its findings. A variety of other engineering researchers and professionals, including members of the Structural Engineering Association of New York, also engaged in the monumental task of collecting data that could lead to a better understanding of the collapse of the buildings themselves and to the development of mitigation strategies to prevent a similar tragedy in the future.

Concerns Related to the Engineering Investigation

Though many of the individuals who have participated in the WTC building performance investigation are architects and engineers with experience investigating other structural collapses—including those resulting from natural causes as well as terrorist attacks—nothing had prepared these investigators for a disaster of this magnitude and complexity. Unlike the destruction caused by an earthquake, which may affect several buildings across an expansive area, this disaster involved many buildings and a massive debris pile in a small, confined area. Also unlike most earthquakes, the WTC disaster caused significant casualties and prompted a prolonged search and rescue effort. In addition, the concurrent criminal investigation by the Federal Bureau of Investigation and a separate investigation by the National Transportation Safety Board further frustrated the building performance investigators.

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The investigation has been hampered by a number of issues, including:

No clear authority and the absence of an effective protocol for how the building performance investigators should conduct and coordinate their investigation with the concurrent search and rescue efforts, as well as any criminal investigation: Early confusion over who was in charge of the site and the lack of authority of investigators to impound pieces of steel for examination before they were recycled led to the loss of important pieces of evidence that were destroyed early during the search and rescue effort. In addition, a delay in the deployment of FEMA’s BPAT team may have compounded the lack of access to valuable data and artifacts.

Difficulty obtaining documents essential to the investigation, including blueprints, design drawings, and maintenance records: The building owners, designers and insurers, prevented independent researchers from gaining access—and delayed the BPAT team in gaining access—to pertinent building documents largely because of liability concerns. The documents are necessary to validate physical and photographic evidence and to develop computer models that can explain why the buildings failed and how similar failures might be avoided in the future.

Uncertainty as a result of the confidential nature of the BPAT study: The confidential nature of the BPAT study may prevent the timely discovery of potential gaps in the investigation, which may never be filled if important, but ephemeral evidence, such as memories or home videotapes, are lost. The confidentiality agreement that FEMA requires its BPAT members to sign has frustrated the efforts of independent researchers to understand the collapse, who are unsure if their work is complementary to, or duplicative of, that of the BPAT team. In addition, the agreement has prevented the sharing of research results and the ordinary scientific give-and-take that otherwise allows scientists and engineers to winnow ideas and strengthen results.

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Uncertainty as to the strategy for completing the investigation and applying the lessons learned: The BPAT team does not plan, nor does it have sufficient funding, to fully analyze the structural data it collected to determine the reasons for the collapse of the WTC buildings. (Its report is expected to rely largely on audio and video tapes of the event.) Nor does it plan to examine other important issues, such as building evacuation mechanisms. Instead, FEMA has asked the National Institute of Standards and Technology (NIST) to take over the investigation. Yet so far, NIST has not released a detailed plan describing how it will take over the investigation, what types of analyses it will conduct, how it will attempt to apply the lessons it learns to try to improve building and fire codes, and how much funding it will require.

Role of the Federal Emergency Management Agency

The Federal Emergency Management Agency is charged with supporting the Nation’s emergency management system. FEMA intervenes at all stages of disaster management including preparation, response, recovery, mitigation, risk reduction, and prevention. In the case of the World Trade Center attack, FEMA dispatched Urban Search and Rescue Teams and established a disaster field office at the site within hours of the first strike to assist in New York City’s rescue effort. At the same time, the FEMA Building Performance Assessment Team (BPAT) began their important work of initiating an analysis that could ultimately yield valuable information about the sequence of events and failures that resulted in progressive building collapse.

BPATs are routinely deployed by FEMA following disasters caused by events such as floods and hurricanes. The teams are formed by, and operate under the direction of the Mitigation Directorate’s Program Assessment and Outreach Division and comprise such individuals as regional FEMA staff, representatives from state and local governments, consultants who are experts in engineering, design, construction, and building codes, and other technical and support personnel. A contractor for FEMA, Greenhorne & O’Mara, Inc., maintains a roster of hundreds of mitigation specialists from across the United States. BPAT teams are typically deployed within seven days of any disaster event.

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Generally, a BPAT conducts field inspections and technical evaluations of buildings to identify design practices, construction methods, and building materials that either failed or were successful in resisting the forces imposed by the event. A major objective of the BPAT’s findings and recommendations are aimed at improving design, construction and enforcement of building codes to enhance performance in future disasters. The culmination of the BPAT’s efforts is a report that presents the team’s observations, conclusions, and recommendations for improving building performance in future natural disasters.

The BPAT team deployed to the WTC site was assembled by the American Society of Civil Engineers and is headed by W. Gene Corley, Ph.D., P.E, Senior Vice President of Construction Technologies Laboratory in Skokie, Illinois. He was also the principal investigator in the FEMA study of Oklahoma City’s Murrah Federal Office Building. On September 11th, ASCE, in partnership with a number of other professional organizations, commenced the formation of an independent team of experts to conduct a building performance assessment study at the WTC site as part of ASCE’s Disaster Response Procedure. In late September, this team, the ASCE Disaster Response team, was officially appointed as the BPAT team and was funded by FEMA to assess the performance of the buildings and report its findings. The BPAT team received $600,000 in FEMA funding in addition to approximately $500,000 in ASCE in-kind contributions.

The 23-member BPAT team conducted an analysis of the wreckage on-site, at Fresh Kills Landfill and at the recycling yard from October 7–12, 2001, during which the team extracted samples from the scrap materials and subjected them to laboratory analysis. Why the analysis was conducted only after a delay of three weeks after the attacks remains unclear. Since November, members of the Structural Engineers Association of New York (SEAoNY) have volunteered to work on the BPAT team’s behalf and are visiting recycling yards and landfills two to three times a week to watch for pieces of scrap that may provide important clues with regard to the behavior of the buildings.

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In the month that lapsed between the terrorist attacks and the deployment of the BPAT team, a significant amount of steel debris—including most of the steel from the upper floors—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—including the suspension trusses from the top of the towers and the internal support columns—were gone before the first BPAT team member ever reached the site. Fortunately, an NSF-funded independent researcher, recognizing that valuable evidence was being destroyed, attempted to intervene with the City of New York to save the valuable artifacts, but the city was unwilling to suspend the recycling contract. Ultimately, the researcher appealed directly to the recycling plant, which agreed to provide the researcher, and ultimately the ASCE team and the SEAoNY volunteers, access to the remaining steel and a storage area where they could temporarily store important artifacts for additional analysis. Despite this agreement, however, many pieces of steel still managed to escape inspection.

The BPAT team is expected to release its report in April. Because FEMA requires the members of its BPAT team to sign a confidentiality agreement until the report is released, the exact scope of the report is unknown. But it appears from the role that BPAT teams normally play and general comments ASCE members of the BPAT team have made that the report is likely to include an examination of how the buildings behaved leading up to the collapse, hypotheses for which structural elements failed and thereby initiated the collapse, and recommendations for additional research and analysis.

For example, ASCE has said that the study will rely primarily on audio and video recordings, interviews with survivors, blueprints and design drawings of the World Trade Center, and evidence they or the SEAoNY volunteers have collected from the rubble. The BPAT team has access to more than 120 hours of high quality film footage and audiotapes of 911 communications with trapped victims. The BPAT team initially had difficulty in obtaining building blueprints and design drawings from either the City of New York, the Port Authority, the building owners, or the building designers due primarily to liability concerns on the part of the building owners and insurers. Belatedly, however, the team was provided access to these documents in early January.

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ASCE has said that the BPAT study will not include an analysis of the evacuation or rescue procedures and may not be able to validate definitively any of a number of hypotheses regarding the collapse. But because of the confidentiality of the report, it is unclear whether the it will provide answers or simply lay out more questions. It is unknown, for example, to what degree the BPAT report will compare video evidence with that collected from the steel beams from the floors that were hit by the planes.

As a result, independent researchers are unsure how they can contribute to the understanding of how the buildings fell without unnecessarily duplicating work. Others fear that the BPAT’s silence on the scope of its report may allow critical aspects of the picture to be missed, and that, by the time the report is released and any such gaps are discovered, the trail of evidence that could provide answers may have grown cold.

The National Science Foundation

Researchers supported by the National Science Foundation are used to mobilizing rapidly after an earthquake and arriving on scene soon after the event to begin collecting data. Recognizing the similarities between the WTC disaster and earthquakes, NSF program managers awarded nearly $300,000 to experienced earthquake researchers, including engineers and social scientists, to begin an analysis of the 9/11 terrorist attacks within 72 hours of the events. In an effort to quickly deploy researchers to the site, awards were made through the Small Grants for Exploratory Research Program, a supplemental award program that enables NSF program managers to award additional support to currently-funded investigators through an abbreviated internal review process (see Appendix B for a list of awards).

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The efforts of NSF-funded researchers were impeded by the same obstacles the BPAT team encountered: an inability to examine the steel, either removed from the site during the early search and rescue work or shipped to recycling plants, and the denial of access to building design, construction and maintenance documents. Interestingly, it was an NSF-funded researcher who ultimately negotiated the arrangements by which he and others investigating the disaster were provided access to the remaining pieces of steel at the recycling plant.

To date, the NSF-funded researchers continue to face problems. They continue to be denied access to important building diagrams and blueprints, and so are unable to complete their analyses or develop the computer models necessary to better understand the failure of the buildings structural elements. Perhaps more importantly, without these computer models, engineering researchers will be unable to develop effective mitigation strategies.

The National Institute of Standards and Technology

NISTs Building and Fire Research Laboratory carries out research in fire science, fire safety engineering, and structural, mechanical, and environmental engineering. It is the only federal laboratory dedicated to research on building design and fire safety. In the past, the lab has investigated several structural failures using authority Congress made explicit in 1985 (15 U.S.C. 282a). The goals of its previous investigations were to determine the probable technical causes of the failures, examine what lessons could be learned from those determinations, and help develop improved building codes, standards, and practices. The investigations also identified areas of research that needed further study.

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Shortly after the attack, NIST appointed an employee of the Building and Fire Research Laboratory to serve on the 23-member BPAT team. While this partnership lent some of NIST’s resources and expertise to the BPAT study, NIST did not immediately launch a formal investigation into the technical causes that led to the collapse of the World Trade Center buildings.

NIST believes that the World Trade Center collapse raises difficult and technical questions regarding building codes and standards, justifying the redirection of funds to its building and fire lab. For example, standards for concrete design, building loads, and structural integrity may need revision. In response, NIST has redirected $2 million of its fiscal year 2002 internal discretionary funds to the lab to supplement its current building engineering and standards work. NIST has also requested permission to reprogram from the rest of its laboratories another $2 million in fiscal year 2002 funds for these efforts. The reprogramming request is currently pending before the Office of Management and Budget and will ultimately need approval from Congress. NIST did not need Congressional review to redirect its discretionary funds. (See Appendix C, Building Design and Collapse Scenarios.)

In January, after a delay of three months since the terrorists’ attacks, FEMA asked NIST to take over the next phase of the investigation of the collapse. Yet neither NIST nor FEMA has released details as to what that next phase would entail (other than the general outline NIST has provided below). In addition, the Administration has not yet indicated whether FEMA, NIST, or a supplemental funding request to Congress would provide funds for such an investigation, nor has it identified how much it would cost.

Administration officials and outside parties are weighing whether a formal arrangement should be made for NIST to serve as FEMA’s research arm in the event of future catastrophic building failures. Currently, there is no formal relationship between the two agencies regarding these matters.

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Based on some initial planning, NIST has preliminarily identified the following general areas for investigation:

Determine technically, why and how the buildings collapsed (WTC 1 and 2, and possibly WTC 7);

Investigate the technical aspects of fire protection, response, and evacuation, and occupant behavior and response;

Determine whether state-of-the-art procedures were used in the design, construction, operation, and maintenance of the WTC building;

Determine whether there are new technologies and procedures emerging that could be employed in the future to reduce the potential risks of collapse; and

Identify building and fire codes, standards, and practices that warrant revision.

3. Questions

Please see Appendix A for copies of letters to witnesses and the questions each was asked to address in testimony at the hearing.

4. Witnesses

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The following witnesses will address the Committee:

Mr. Robert Shea, Acting Administrator Federal Insurance and Mitigation Administration, and, Mr. Craig Wingo, Director of Division of Engineering Science and Technology, Federal Emergency Management Administration

Dr. W. Gene Corley, P.E., S.E., American Society of Civil Engineers, Chair of the Building Performance Assessment Team reviewing the WTC disaster

Professor Glenn Corbett, Assistant Professor of Fire Science at John Jay College, New York City

Dr. Abolhassan Astaneh-Asl, Professor, Department of Civil and Environmental Engineering, University of California, Berkeley

Dr. Arden Bemet, Director, National Institute of Standards and Technology

5. Additional Reading

Glanz, J. (2001, December 4). Wounded Buildings Offer Survival Lessons. The New York Times, p. F1

Glanz, J., & Lipton, E. (2001, December 25). A Nation Challenged: The Towers; Experts Urging Broader Inquiry in Towers’ Fall. The New York Times, p. A1

Glanz, J., & Lipton, E. (2002, January 17). New Agency to Investigate the Collapse of Towers. The New York Times, p. B3

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Glanz, J., & Lipton, E. (2002, February 2). At Scrapyards, as Search for Clues in the Towers’ Collapse. The New York Times, p. B1

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Chairman BOEHLERT. Good afternoon. I want to welcome everyone here today to our second hearing on the collapse of the World Trade Center. In many ways this hearing is a continuation of the discussions we began at our first hearing on March 6. And, indeed, we have the exact same panel of witnesses before us today as we did two months ago.

On March 6, we delved into the procedures that were followed to assess what had caused the towers to collapse in those indelible moments of September 11. We were not happy with what we learned. We found that the study of the collapse had been hampered by bureaucratic confusion, hesitation, and delay, by a lack of investigative tools, and by excessive restrictions on the flow of information.

But we also learned that despite these severe impediments, the team lead by the American Society of Civil Engineers, as well as other researchers, was able to draw some preliminary conclusions about the collapse, and the National Institute of Standards and Technology was willing to pick up where the ASCE team had left off, even though NIST officials couldn’t tell us much, at that point, about exactly what that meant.

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Today, we will pick up the story where we left off, focusing on three issues. First, the ASCE team will describe the conclusions of their study and it will become the subject of full-blown public deliberation for the first time. Second, NIST will tell us exactly what it intends to do in its follow-up investigation, for which the Administration has requested $16 million. And, third, we will release and open up the public discussion on legislation to ensure that the problems that hamstrung the ASCE study never, ever recur.

Let me first turn to the legislation, which I have drafted with my colleague, Mr. Weiner. The bill, known as the National Construction Safety Team Act, is designed to remedy each and every impediment that was encountered in the Trade Center investigation.

At the March 6 hearing, we uncovered four ways in which the status quo was unacceptable. First, no Federal agency was clearly charged with investigating building failures. The bill solves that problem by giving NIST clear responsibility to handle the investigations. Second, nothing ensured that investigations would begin quickly enough to preserve valuable evidence. The bill solves that problem by requiring NIST to act within 48 hours of a building failure.

Third, no Federal agency had the investigative authority it needed to ensure access to all needed information. The bill solves that problem by giving NIST clear authority to enter sites, access documents, test materials, and move evidence, as well as clear authority to issue subpoenas. Fourth, nothing ensured that the public was kept informed of the progress of the investigation. The bill solves that problem by requiring NIST to provide regular public briefings and to make public its findings and the materials that led to those findings.

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We listened closely on March 6 and we have responded with a measure targeted precisely to remedy the issues that came to our attention. And we based the bill on a highly successful model, the National Transportation Safety Board, the Federal agency that investigates airline crashes.

We want to begin to get comments on the draft bill today, and we intend to introduce it, along with several colleagues on this Committee, and my colleagues from New York, Senators Clinton and Schumer, within the week. I expect our Committee to approve the bill by the end of the month and I would like to see it come to the House Floor as soon as possible.

While the bill is mostly prospective in its focus, all the investigative tools it would provide to NIST, including subpoena power, would be available to conduct the World Trade Center investigation.

But what will that investigation entail? That is the key question this Committee needs to pursue today with NIST. There is an almost unlimited universe of questions that NIST could address, but time and money are not unlimited. NIST needs to focus on those matters that are most likely to result in changed codes and practices, including evacuation and emergency response procedures in a wide variety of buildings.

The investigation can’t be driven by mere curiosity or political pressures. And it can’t be based on the assumption that unlimited dollars will flow for future research. It has to be driven by the desire to save the maximum number of lives in the future and to make the changes needed to save those lives as rapidly as possible. I hope that NIST will be able to assure us today that it is doing exactly that.

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But regardless of the precise NIST agenda, the lab needs the $16 million that the Administration has requested for it in the supplemental appropriations bill that the House will consider later this month. The Administration is to be applauded for this request, although they have unfortunately complicated matters by asking that the money be provided to FEMA for transfer to NIST. We will work with the appropriators to get this money to NIST directly if possible; indirectly, if necessary. I don’t really see why we have to go to FEMA, then to NIST. Why not directly to NIST?

So we still have plenty of questions as we pick up where we concluded on March 6. I want to assure the public in general, but especially the families of the victims, that this panel is committed to following this issue in the months and years ahead. We will not rest until we learn all we need to know to prevent future tragedies and until we implement what we have learned.

Let me conclude the same way I did on March 6. We are here because the only way to move forward is to try to understand what happened on a day that was so incomprehensible. With that, the Chair recognizes Mr. Hall.

[The prepared statement of Mr. Boehlert follows:]

PREPARED STATEMENT OF CHAIRMAN SHERWOOD BOEHLERT

I want to welcome everyone here today to our second hearing on the collapse of the World Trade Center. In many ways, this hearing is a continuation of the discussions we began at our first hearing on March 6, and, indeed, we have the exact same panel of witnesses before us today as we did two months ago.

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On March 6, we delved into the procedures that were followed to assess what had caused the towers to collapse in those indelible moments of September 11th. We were not happy with what we learned. We found that the study of the collapse had been hampered by bureaucratic confusion, hesitation and delay; by a lack of investigative tools and by excessive restrictions on the flow of information.

But we also learned that, despite these severe impediments, the team led by the American Society of Civil Engineers (ASCE), as well as other researchers, were able to draw some preliminary conclusions about the collapse, and that the National Institute of Standards and Technology (NIST) was willing to pick up where the ASCE team had left off, even though NIST officials couldn’t tell us much at that point about exactly what that meant.

Today, we will pick up the story where we left off, focusing on three issues.
First, the ASCE team will describe the conclusions of their study—and it will become the subject of full-blown, public deliberation for the first time.

Second, NIST will tell us exactly what it intends to do in its follow-up investigation, for which the Administration has requested $16 million.

And third, we will release and open up the public discussion on legislation to ensure that the problems that hamstrung the ASCE study never, ever recur.

Let me turn first to the legislation, which I have drafted with Mr. Weiner. The bill, known as the ”National Construction Safety Team Act,” is designed to remedy each and every impediment that was encountered in the Trade Center investigation.

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At the March 6 hearing, we uncovered four ways in which the status quo was unacceptable. First, no federal agency was clearly charged with investigating building failures. The bill solves that problem by giving NIST clear responsibility to handle the investigations. Second, nothing ensured that investigations would begin quickly enough to preserve valuable evidence. The bill solves that problem by requiring NIST to act within 48 hours of a building failure. Third, no federal agency had the investigative authority it needed to ensure access to all needed information. The bill solves that problem by giving NIST clear authority to enter sites, access documents, test materials and move evidence, as well as clear authority to issue subpoenas. Fourth, nothing ensured that the public was kept informed of the progress of the investigation. The bill solves that problem by requiring NIST to provide regular public briefings and to make public its findings and the materials that led to those findings.

We listened closely on March 6, and we have responded with a measure targeted precisely to remedy the issues that came to our attention. And we based the bill on a highly successful model—the National Transportation Safety Board, the federal agency that investigates airline crashes.

We want to begin to get comments on the draft bill today, and we intend to introduce it—along with several colleagues on this Committee and in the Senate—within about a week. I expect our Committee to approve the bill by the end of the month, and I would like to see it come to the House floor as soon as possible.

While the bill is mostly prospective in its focus, all the investigative tools it would provide to NIST, including subpoena power, would be available to conduct the World Trade Center investigation.

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But what will that investigation entail? That’s the key question this Committee needs to pursue today with NIST. There is an almost unlimited universe of questions that NIST could address, but time and money are not unlimited. NIST needs to focus on those matters that are most likely to result in changed codes and practices—including evacuation and emergency response procedures—in a wide variety of buildings.

The investigation can’t be driven by mere curiosity or political pressures, and it can’t be based on the assumption that unlimited dollars will flow for future research. It has to be driven by the desire to save the maximum number of lives in the future—and to making the changes needed to save those lives as rapidly as possible. I hope that NIST will be able to assure us today that it is doing exactly that.

But regardless of the precise NIST agenda, the lab needs the $16 million that the Administration has requested for it in the Supplemental Appropriations bill that the House will consider later this month. The Administration is to be applauded for this request, although they have, unfortunately, complicated matters by asking that the money be provided to FEMA for transfer to NIST. We will work with the appropriators to get this money to NIST—directly, if possible; indirectly, if necessary.

So we still have plenty of questions as we pick up where we concluded on March 6. I want to assure the public in general, but especially the families of the victims, that this panel is committed to following this issue in the months and years ahead. We will not rest until we learn all we need to know to prevent future tragedies and until we implement what we have learned.

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Let me conclude the same way I did on March 6: We are here because the only way to move forward is to try to understand what happened on a day that was so incomprehensible.

Mr. HALL. Mr. Chairman, I certainly want to join you, as our chairman, in welcoming everyone to this Committee, and you and Mr. Weiner, and others who have worked on your legislation. It is sensible, necessary, humanitarian legislation, as you alluded to 9/11, the day that terrorists declared war on this country with a dastardly act. We had loss of life there of people that may never even have enough of a body to have a decent funeral. Unbelievable tragedy that was forced and thrust upon us.

And I think, for those people—you know, like in World War I, World War II, when we lost a person, young or old—for those people who lost someone, that war never ends. It is there with them until they find closure. And they can only find closure through information and action. And you have to have the tools to make that happen.

Today, we are going to focus on the findings and recommendations of the Building Performance Assessment Team and the National Institute of Standards and Technology’s follow-on legislation and their research agenda, which is so necessary. And while I commend the team for their outstanding commitment and effort, their report highlights that a lot remains to be done, and that is where NIST comes in.

I hope to find out today whether they have the funding required to do a complete investigation. And I am certain that all the Committee members are united in ensuring that the required funds are provided to NIST.

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And, finally, I want to welcome the members of the Skyscraper Safety Campaign and thank them for their contributions to the Committee’s work. I want to, again, commend Chairman Boehlert for his leadership on this issue, his interest in this issue, his support of this issue, and his reaching out to work with all the members of the Committee.

And I want to yield to Representative Weiner who has a direct interest and thrust into this and to recognize Steve Israel and John Larson who had constituents that were killed on that dreadful day. But right now, I want to yield my time to Congressman Weiner, and I think he will handle the time and share some with Steve Israel. With that, Mr. Chairman, I thank you, and I thank all of you for what you are doing and what you will do.

[The prepared statement of Mr. Hall follows:]

PREPARED STATEMENT OF REPRESENTATIVE RALPH M. HALL

I want to join Chairman Boehlert in welcoming everyone to the Committee second hearing on the World Trade Center building investigation.

Today, we will focus on the findings and recommendations of the Building Performance Assessment Team and the National Institute of Standards and Technology’s follow-on research agenda. While I commend the Team for their outstanding commitment and effort, their report highlights that much remains to be done—this is where NIST comes in. I hope to find out today whether they have the funding required to do a complete investigation. I am certain that all the Committee Members are united in ensuring that the required funds are provided to NIST.

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Finally, I want to welcome members of the Skyscraper Safety Campaign and thank them for their contributions to the Committee’s work.

I also want to commend Chairman Boehlert for his leadership on this issue and for reaching out to work with all the Members of the Committee.

Now, I yield the balance of my time to Rep. Weiner from New York City who has been working with Chairman Boehlert on legislation addressing building investigations.

Chairman BOEHLERT. Thank you very much. The gentleman recognizes the gentleman from New York, my colleague, Mr. Weiner, with whom we have worked hand-in-glove on a bipartisan basis to deal in a responsible and timely manner with this issue. Mr. Weiner.

Mr. WEINER. Thank you very much, Mr. Chairman. And I think that when this chapter is written, your leadership will be recognized in keeping this issue on the front burner and making sure we, in Congress, act to solve the problems. You know, no one would dispute that the attack on the World Trade Center could not have been anticipated. In many respects, we can only marvel at the skill of the designers of the Twin Towers and the workmanship of the thousands of nameless and faceless steel workers and laborers who constructed it.

Thousands of families will enjoy dinner together tonight because even under the most unimaginable circumstances, these proud buildings stood tall for more than an hour. But for the families of those lost, today’s report offers little consolation and leaves many questions unanswered. And, sadly, because of the early missteps in the investigation, some of the most vexing questions may never be unraveled.

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Thousands of tons of steel were carted away and recycled before any expert could examine what could have been telltale clues. Support trusses, fireproofing fragments, and even burned-out electrical switches that might have given scientists and engineers insight were lost forever even before an investigation was underway.

Ladies and gentlemen, this amounts to what is, indeed, a crime scene investigation. Yet, not only is there no smoking gun, there wasn’t even a weapon found. There weren’t even fingerprints taken, and, if truth be told, there wasn’t even a detective assigned to the case until very late in the process.

The report is short on conclusions about design decisions that could have contributed to the deaths of so many firefighters and workers on the top floors. Should future buildings avoid the concentration of stairwells that were used in the Twin Towers? Was enough attention given to the communications infrastructure that failed once after the 1993 bombings of these same buildings, and tragically left hundreds of emergency workers climbing stairs up while officials on the ground knew that the buildings were about to come down?

Did the fireproofing separate from the steel because of the intense heat, or was it the design of this post-asbestos treatment that is in place in thousands of buildings and did this fail for other reasons?

We cannot bring back those lost on September 11. And today there are more than 25,000 mothers, fathers, aunts, uncles, fiancees, and loved ones who, thank God, escaped that day. But if we want to ensure that the legacy of this tragedy is that future building collapses are avoided or mitigated, then we need to do a better job of investigating the causes.

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We pray that no other plane ever crashes into a tall building and we hope that an earthquake never rattles our skyscrapers. And we remain vigilant against the threat of a bomb in our city centers. But just as we are not satisfied to simply hope another plane doesn’t crash, we need to create an investigative team, like the NTSB, to jump into action, to investigate building collapses, protect and preserve evidence, issue regular briefings, and reach conclusions that formalize standards for building design, egress, and emergency escape.

Chairman Boehlert, whose leadership I have already noted, and I are going to be introducing legislation that will create this new authority. I urge my colleague and the President to support this effort. And I yield what brief time I may have left to Mr. Israel for a few remarks, as well.

Chairman BOEHLERT. And you don’t have any time left, but Mr. Israel will be recognized in a moment. We want to do it on a back and forth——

Mr. WEINER. Thank you, Mr. Chairman.

[The prepared statement of Mr. Weiner follows:]

PREPARED STATEMENT OF REPRESENTATIVE ANTHONY WEINER

No one would dispute that the attack on the World Trade Center could not have been anticipated. In many respects one can only marvel at the skill of the designers of the Twin Towers and the workmanship of the thousand nameless steelworkers and laborers.

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Thousands of families will enjoy dinner together tonight because even under the most unimaginable of circumstances these proud buildings stood tall for more than an hour. But for the families of those who were lost, the report released today by FEMA offers little consolation and leaves many questions unanswered. And sadly, because of early missteps in the investigation, some of the most vexing questions may never be unraveled.

No one would dispute that the attack on the World Trade Center could not have been anticipated. In many respects one can only marvel at the skill of the designers of the Twin Towers and the workmanship of the thousands of nameless steelworkers and laborers.

Thousands of tons of steel were carted away and recycled before any expert could examine what could have been tell-tale clues. Support trusses, fireproofing fragments and even burnt out electrical switches that might have given scientists and engineers insight were lost forever—even before an investigation was underway.

The report is short on conclusions about design decisions that may have contributed to the deaths of so many firefighters and workers on the top floors. Should future buildings avoid the concentration of stairwells that were used in the Twin Towers? Was enough attention given to the communications infrastructure that failed in the 1993 bombing and tragically left hundreds of emergency workers climbing stairs while officials on the ground knew that the buildings were about to come down? Did the fireproofing separate from the steel beams because of the intense heat or is the design of this post-asbestos treatment—that is in place in thousands of buildings—fail for other reasons?

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We cannot bring back those who were lost on September 11th. And today there are more than 25,000 mothers, fathers, aunts, uncles, fiancées and loved ones who we thank god escaped that day. But if we want to ensure that the legacy of this tragedy is that future building collapses are avoided or mitigated—we need to do a better job of investigating the causes.

We pray that no other plane ever crashes into a tall building. And we hope that an earthquake never rattles our nation’s high rises. And we remain vigilant against the threat of a bomb in our city centers.

But we are not satisfied to simply hope that another plane crash doesn’t occur. Rather, we need to create an investigative team like the NTSB to jump into action to investigate building collapses, protect and preserve evidence, issue regular briefings, and reach conclusions that formalize standards for building design, egress and emergency escape.

Chairman Boehlert, whose leadership on this issue has provided comfort to all the victims’ families, and I will be introducing legislation to create this new authority.

I urge my colleagues and the President to support this effort.

Chairman BOEHLERT Follow usual procedure, to demonstrate to everyone how well we work together——

Mr. WEINER. Thank you, sir.

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Chairman BOEHLERT On a bipartisan basis. The Chair recognizes Ms. Morella.

Ms. MORELLA. I thank you, Mr. Chairman. And I certainly thank you for calling this important hearing to follow up on our work of a couple of months ago. In March, we heard disturbing testimony on the investigation into the World Trade Center collapse—questions of jurisdiction, availability of evidence, and the scope of the inquiry surrounding the investigation leading to grave concerns from what we heard about the victims’ groups and the public at large.

All the witnesses testified to the problems they encountered during the investigation and the need for further study into additional areas, new authority to investigate and deal with future catastrophes. And through your leadership, Mr. Chairman, the Science Committee has taken up these challenges. I believe that we have a strong blueprint for future action. I also thank Mr. Weiner for his work on this and Mr. Hall and others.

The attack on our Nation was truly unprecedented. The horror of the collapse of the Twin Towers will be etched on our minds for generations. And, yet, while we should never forget the rage and anger that we felt from this atrocity, we should also remember the heroic actions of everyday people.

And I know we have a number of people who are here today who are most affected by the tragedy of September 11. I want to offer my condolences for their loss, thank them for their sacrifices, applaud them for their perseverance. You are what makes this country great.

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Today we are going to do three very important things. First, the release of the Building Performance Assessment Team report on the collapse of the World Trade Center. These men and women performed under difficult conditions without a clear mandate. Their investigation did not go smoothly.

Secondly, we will unveil NIST’s plan for the future, acting on recommendations from BPAT, as well as a host of scientists, professional organizations, and other individuals. The National Institute of Standards and Technology has developed a comprehensive plan for an in-depth building and fire safety investigation into the collapse of the Twin Towers, as well as a multi-year research and development program to provide technical support to improve building and fire codes, standards, and practice. And, of course, NIST is the premier facility for research in building design and safety, and it is uniquely positioned to conduct this extensive investigation that would be necessary.

And, finally, the Science Committee has been hard at work providing the infrastructure and authority to conduct investigation into future events. And the draft today of the National Construction Safety Board Act to empower a team of investigators to conduct inquiries into building failures, in much the same way as the NTSB conducts investigation of airline crashes and other transportation disasters, is very important. The legislation specifically addresses the problems of authority and jurisdiction associated with the BPAT investigation and will provide a clear chain of command for future work.

Again, I commend you, Mr. Chairman, Mr. Weiner, and Mr. Hall. I am pleased to be an original cosponsor with you on that bill. I yield back, and thank you for the courtesy.

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[The prepared statement of Ms. Morella follows:]

PREPARED STATEMENT OF REPRESENTATIVE CONSTANCE MORELLA

Mr. Chairman, thank you for calling this important hearing to follow up on our work of two months ago. In March, we heard disturbing testimony on the investigation into the World Trade Center collapse. Questions of jurisdiction, the availability of evidence, and the scope of the inquiry surrounded the investigation, leading to grave concerns among the victim’s groups and the public at large. All the witnesses testified to the problems they encountered during the investigation, the need for further study into additional areas, and the need for new authority to investigate and deal with future catastrophes. Through your leadership, the Science committee has taken up these challenges and I believe we have a strong blueprint for future action.

The attack on our nation was truly unprecedented. The horror of the collapse of the twin towers will be etched on our minds for generations. And yet, while we should never forget the rage and anger we felt from this atrocity, we should also remember the heroic actions of everyday people. Men and women who lost their lives helping others for no other reason than because its their job. Men and women who came together to provide aid to the survivors and comfort to the grief stricken. America’s worst moment may have come on a fateful morning in September, but some of its best have been coming for the past eight months. We have a number of people here today who were most affected by the tragedy of September and I want to offer my condolences for their loss, thank them for their sacrifices, and applaud them for their perseverance. You are what make this country great.

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Today we do three very important things. First, we will herald the release of the Building Performance Assessment Team Report on the collapse of the World Trade Center. These men and women performed under difficult conditions and without a clear mandate. Their investigation did not go smoothly. Their was difficulty in accessing important records and material, information was not shared in a timely fashion, and the community was left out of the loop. Nevertheless, these problems were not because of the dedicated individuals conducting the study. They have worked hard and done the best with what they could do. What’s more, they have been honest about their limitations and freely discussed the deficiencies in their report and called for further action. They have not swept the issues under the rug, but rather brought the problems out into the light. I realize that this small comfort to those suffering now, but it is imperative to avoid the same mistakes and the same suffering in the future. I commend them for their integrity and for their effort.

Second, we will unveil NIST’s plan for the future. Acting on recommendations from BPAT as well as a host of scientists, professional organizations, and other individuals, the National Institute for Standards and Technology have developed a comprehensive plan for a in-depth building and fire safety investigation into the collapse of the Twin Towers as well as a multi-year research and development program to provide technical support to improve building and fire coeds, standards, and practices. NIST is the premier federal facility for research in building design and safety, and they are uniquely positioned to conduct the extensive investigations necessary to fully understand the World Trade Center collapse and prevent future disasters. With NIST at the helm, we are in very good hands.

Finally, the Science Committee has been hard at work providing the infrastructure and authority to conduct investigation into future events. Today we are releasing a draft of the ”national Construction Safety Board Act” which will empower a team of investigators to conduct inquiries into building failures in much the same way the NTSB conducts investigation of airline crashes and other transportation disasters. The legislation specifically addresses the problems of authority and jurisdiction associated with the BPAT investigation and will provide a clear chain-of-command for future work.

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I want to thank the witness for agreeing to appear before us today and am looking forward to your comments on NIST’s plan as well as our proposed legislation.

Chairman BOEHLERT. Thank you so much, Ms. Morella. The Chair recognizes Mr. Israel.

Mr. ISRAEL. I thank the Chairman. I thank the Chairman for his customary bipartisanship and the wisdom with which he leads this Committee. Mr. Chairman, on September 11, Susan Clyne of Lindenhurst went to her desk at the World Trade Center and lost her life. On September 11, Ray Downey of Deer Park went to try and save Ms. Clyne’s life and lost his life as the third highest ranking member of the New York City Fire Department. I represent over 100 families who lost a loved one in the rubble of the World Trade Center.

This report is important to them, but while it may answer some questions about what happened that day, it leaves many other questions unanswered, particularly as it pertains to protecting against such a calamity in the future, especially when it comes to reviewing and changing our building codes.

Let me very briefly share just three sentences from the report with my colleagues that I believe are fundamentally important. The report notes that during the course of this study, the question of whether building codes should be changed in some way to make future buildings more resistant to such attacks, was frequently explored.

It goes on to note that the BPS team felt that extensive technical policy and economic study of these concepts should be performed before any specific code change recommendations are developed. This report specifically recommends such additional studies. Future building code revisions may be considered after the technical details of the collapses and other building responses to damage are better understood.

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The report raises the question of how building codes should be changed to withstand the potential of future attacks, but it fails to really answer it. It calls for additional studies. And the problem, as I see it, is that some at NIST are recommending a $40 million study to truly embrace all of the building code issues, while others are recommending 1/10 of that. We can’t shortchange every American who enters any American building in the future.

The Chairman is absolutely correct. Time and money are not limitless, but I believe that we have a fundamental obligation to learn from the past, to act on the future, and to invest in the basic premise of keeping Susan Clyne and Ray Downey, and every American who goes to their jobs in a tall building and sits behind their desks, free from this kind of attack in the future. I thank the Chairman and I thank my colleague, Mr. Weiner, and I look forward to continuing to work with them.

Chairman BOEHLERT. Thank you very, Mr. Israel. And the Chair will now recognize—and this the final recognition—Mr. Grucci. The Chair is recognizing those members of the panel that have been most active in working on this legislation and have been most directly affected because of constituencies. All members will have an opportunity to have their full statements appear in the record at this juncture. With that, the Chair recognizes Mr. Grucci, my colleague from New York.

Mr. GRUCCI. Thank you, Mr. Chairman. And I, too, want to congratulate you for your leadership on this issue, a very, very important issue, and my colleagues who have been working on this. Mr. Weiner, thank you for your leadership.

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I, too, represent a district where a number of families have lost loved ones, whether they were working in the building or working to try and save people in the building. And it has been a very difficult and a very tough time for all of America and certainly for those families who have to now live this horrible, horrible experience throughout the rest of their days.

And to that end, the Nation has embraced New York in the greatest time of its need. As we continue to come to grips with the horrific terrorist attacks of September 11, the tragedy that took place at the World Trade Center was one of unimaginable magnitude. We saw the best of New York: communities joining together to aid their families, friends, and people who they have never met. Now, more than 8 months after that fateful morning, we continue to work together to see that a tragedy like this never happens again.

I am proud to be an active part of the Science Committee’s investigation into this tragedy and look forward to hearing from our witnesses. I have placed my full support behind this legislation and I am working closely with Chairman Boehlert to make this bill the best it can possibly be. I am interested in learning the findings and the recommendations from NIST and the Building Performance Assessment Team, and I am committed to working with the Committee and the investigative team to complete a full investigation. I wish to recognize the presence of the many victims’ families and applaud you for your dedication and I stand with you in this very difficult time.

Thank you, Mr. Chairman, for your leadership on this hearing and in the investigation. And from one New Yorker to another, thank you for your commitment to these families and to all those who have lost loved ones in this tragic event, this terrorist attack of September the 11th. And we will work until we find a way to ensure that people will be safe when they go to work. Thank you, Mr. Chairman. And I yield back the remainder of my time.

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[The prepared statement of Mr. Grucci follows:]

PREPARED STATEMENT OF REPRESENTATIVE FELIX J. GRUCCI, JR.

Thank you Mr. Chairman.

The Nation has embraced New York in its greatest time of need, as we continue to come to grips with the horrific terrorist attacks of September 11.

The tragedy that took place at the World Trade Center was one of unimaginable magnitude. We saw the best of New York, communities joining together to aid their families, friends, and even complete strangers. Now, more than eight months after that fateful morning, we continue to work together to see that a tragedy like this one may never happen again.

I am proud to be an active part of the Science Committee’s investigation into this tragedy and look forward to hearing from our witnesses. I have placed my full support behind the legislation and am working closely with Chairman Boehlert to make this the best bill possible. I am interested to learn the findings and recommendations from NIST and the Building Performance Assessment Team, and am committed to working with the Committee and investigative teams to complete a full investigation. I wish to recognize the presence of many of the victim’s families and applaud you for your dedication and stand with you in this difficult time.

Thank you Mr. Chairman for your leadership on this hearing and investigation, and from one New Yorker to another, thank you for your commitment to New York.

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I yield back the balance of my time.

[The prepared statement of Ms. Lee follows:]

PREPARED STATEMENT OF REPRESENTATIVE SHEILA JACKSON LEE

Mr. Speaker,

I would like to thank you for holding this hearing today and I would also like to thank the distinguished group of witnesses who have taken the time to join us again and share their knowledge on this issue.

The National Institute of Science and Technology (NIST) has recently informed the Committee of prepared initial plans for its own investigation, and the Administration has requested supplemental funding of $16 million to pay for NIST’s investigation. However, I am concerned about additional issues which have arisen in recent weeks, such as the point that the FEMA designated building performance assessment (BPAT) report is a start but more work needs to be done with an expanded expert-driven committee.

The main reason for the numerous hearings the Committee has held and the time and effort invested into this topic is prevention and readiness for a possible future attack. Therefore, I am especially curious as to the circumstances under which FEMA would ask the NIST for assistance.

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Secondly, it is unclear whether the second phase of NIST’s follow-up plans—a 3-year research effort to determine whether and how changes in building codes should be made—will receive the commitment for funding it requires. In addition to conducting a $16 million follow-up investigation to collect more data regarding the Trade Center disaster, NIST also proposes to conduct longer-term research on issues identified by the building performance assessment team (BPAT) report. For example, NIST plans to develop computer models of the collapse and conduct experiments to better understand the effect of fire on steel connections in buildings.

NIST estimates, however, that the total cost of the program will be approximately $40 million over the next three years. While NIST has said that some funds may be contributed by private sources, it is unclear if any such commitments have been made.

If adequate funding for NIST’s research efforts are not secured it is unclear how NIST will use the information it collects in its investigation to improve standards, practices and codes for buildings and fire.

I hope that some of the distinguished guests here today will able to clear up some of the vagueness that surrounds this issue, which is obviously of great importance to this committee.

Thank you.

Chairman BOEHLERT. Thank you very much. And I want to thank all of my colleagues for their very thoughtful presentations. Now, we are going to go forward with our panel of expert witnesses and, gentlemen, I thank you all for the dedication you have evidenced to this important task. You were all here on March 6. We listened. We learned. We are here to listen again and we are here to learn, but we are also here to act.

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What we are going to do is give the panel varying time allocations. Dr. Corley, you are going to get the most time because you are going to talk about the study, and we will give you 15 minutes. And the Chair will not be arbitrary, but would ask you to try to summarize in 15 minutes. Dr. Bement, we will have you talk about where we are going from here with NIST, and we will give you 10 to 15. And then, Mr. Shea, and, Professor Corbett, we would ask that you try to have five minutes or so, but if you need more—this is too darn important to have some clock ticking away, saying, well, you have got to stop and summarize in 60 seconds or less. So we are going to give you the time you need, but we want to be mindful of the interest of the panel and getting some questions in.

And then, finally, Dr. Barnett, you are here as a resource to Dr. Corley, as I understand it. And you are a two-tag team. Is that how it is going to work? You determine how that will work. Mr. Shea, you are up first. Mr. Robert Shea, Acting Administrator, Federal Insurance and Mitigation Administration.

STATEMENT OF MR. ROBERT F. SHEA, ACTING ADMINISTRATOR, FEDERAL INSURANCE AND MITIGATION ADMINISTRATION, FEDERAL EMERGENCY MANAGEMENT AGENCY

Mr. SHEA. Thank you, Mr. Chairman, Members of the Committee. I respectfully request that my written testimony be entered into the record and that I be allowed to make a very brief opening statement.

Chairman BOEHLERT. Without objection, all the formal presentations will be in the record at this juncture in their entirety, and we appreciate your willingness to try to summarize and highlight.

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Mr. SHEA. Thank you, Mr. Chairman. Today, we will examine the reasons why the World Trade Center collapsed as a result of the horrendous terrorist act. However, nothing that we do today will explain the human tragedy. It is that tragedy that brings us together today. Dr. Corley and his team are to be commended. Never have we dealt with a report of this complexity in this length of time. All of us were spurred by the events of September 11. After today, as been noted by the Chairman and others, much remains to be done, and particularly, I think, by Dr. Bement and his team at the National Institute of Standards and Technology. FEMA stands ready to assist at this point.

Nonetheless, we remain compelled by the human tragedy. And I want to thank the Committee, and particularly the families and the heroes and victims, for their patience and their understanding. Thank you, Mr. Chairman.

[The prepared statement of Mr. Shea follows:]

PREPARED STATEMENT OF ROBERT F. SHEA

Mr. Chairman, Members of the Committee, I appreciate the opportunity to appear before you today to discuss the Federal Emergency Management Agency’s Building Performance Assessment Team. My name is Robert Shea, Acting Administrator for the Federal Insurance and Mitigation Administration, and I am here representing Joe Allbaugh, the Director of the Federal Emergency Management Agency (FEMA).

At the Committee’s March 6th hearing, FEMA described the engineering study of the tragic collapse of the World Trade Center, which was caused by terrorists inflicting a direct attack on America. This study and report have been completed with unprecedented speed. All our previous work pales by comparison. I am pleased that we are able to present this document to the Committee today. The Committee provided extremely helpful direction to FEMA during the last hearing that has assisted us in moving forward to complete this initial report.

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To achieve a broader review of the FEMA/ASCE World Trade Center study, FEMA asked the witnesses from the last hearing to review and provide comments on the report. Additionally, FEMA asked the National Science Foundation (NSF) to identify reviewers to evaluate and comment on the report. ASCE arranged for additional outside reviewers from various technical committees from within ASCE. I invited Chief Ed Stinnette, Chief of the Fairfax County Fire Department in Virginia, to participate in this outside review of the report, as well. The BPAT team considered every single comment and made modifications to the report, where appropriate. FEMA is genuinely appreciative of the contributions from these reviewers because this process has helped to ensure that this report is well rounded and will serve as a stable foundation upon which the National Institute of Standards and Technology (NIST) can embark on its long-term investigation.

Chief Stinnette provided particularly valuable insights, showing the importance of the fire service, including the United States Fire Administration, in the future work that the NIST has proposed. The National Science Foundation Review process for the report was extremely productive and well supported by Dr. Rita Colwell and Dr. Priscilla Nelson at NSF. We will take advantage of this review process for any similar future efforts that we are engaged in.

All of the reviewers were given the option of addressing a letter to me on major public policy issues to be included as an Appendix to the report. No reviewer accepted this offer.

FEMA has signed a Memorandum of Understanding (MOU) with NIST that will help to guide our future collaborations on similar types of studies, and we are committed to work with NIST and NSF to identify how we can. For these types of extreme events, whether natural or man-made, the MOU will serve as a road map to establish protocols for future collaboration of our two agencies under our respective authorities.

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Dr. Gene Corley, the BPAT Team leader, is to be commended. He and the Team have done remarkable work. They have done a great service for this country. I would also like to recognize the very real contribution that the prime contractor has made, Greenhorne and Omara. The report would not have been available today without their support.

Finally, I want to thank the Committee and, particularly, the families for their patience.

I would now be pleased to answer any questions that the Committee may have.

BIOGRAPHY FOR ROBERT F. SHEA

Robert F. Shea was appointed Acting Administrator of the Federal Insurance and Mitigation Administration in August 2001 after an agency-wide reorganization. Previously, Mr. Shea was deputy administrator for mitigation in FEMA. In his acting capacity, Mr. Shea is responsible for overseeing the insurance and risk reduction activities of FEMA, including educating residents and state and local official about the importance of risk reduction activities. Mr. Shea also coordinates efforts to educate the public on the importance of insuring property against flood damage.

Previously, Mr. Shea served as the Division Director for the Program Support Division within FEMA’s then-Mitigation Directorate. In that capacity, he provided executive direction to the Hazard Mitigation Planning Program, the Hazard Mitigation Grant Program and the Flood Mitigation Assistance Program.

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Mr. Shea has spent 25 years in emergency management in FEMA, serving in various capacities, including chief of the Coordination Office of the former State and Local Program and Support Directorate and chief of the Program Development Division in the former Office of Earthquakes and Natural Hazards.

A native of Atlanta, Ga., Mr. Shea earned Bachelor’s and Masters’s degrees in English Literature from The Catholic University of America.

Chairman BOEHLERT. Thank you very much. Dr. Gene Corley, American Society of Civil Engineers. Dr. Corley is the Chair of the Building Performance Assessment Team, which has reviewed the WTC disaster. And let me say, the Nation owes a debt of gratitude to you and your outstanding organization, the American Society of Civil Engineers. We appreciate very much what you are doing. The task isn’t over, as you well know. And with that, Dr. Corley, the floor is yours.

STATEMENT OF DR. W. GENE CORLEY, P.E., S.E., CTL ENGINEERING, CHICAGO, ILLINOIS, ON BEHALF OF THE AMERICAN SOCIETY OF CIVIL ENGINEERS, CHAIR OF BUILDING PERFORMANCE ASSESSMENT TEAM REVIEWING THE WORLD TRADE CENTER DISASTER; ACCOMPANIED BY DR. JONATHAN BARNETT

Dr. CORLEY. Thank you, Mr. Chairman. If you will permit me, I do have some illustrations that will be shown as I speak. I would like to start by just commenting that during our work on the team the tragedy that occurred was uppermost in our mind, and continually we recognize the losses of those who were in the buildings and the loss forever to those who remain behind. The work that we did was intended to help those in the future.

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Over the next few minutes, I will first describe briefly the composition of the team and give a short illustration of some of the tools we used, but I will concentrate mostly on the important findings that we have and the recommendations we have for the NIST study.

Our team was made up of approximately 25 people. Among these members of the team were structural engineers, designers, analysts, professors, my colleague, Dr. Jonathan Barnett, and we also had firemen on the team, investigators, a wide range of expertise to do this work.

The scope of the investigation was not to come to final conclusions. We simply didn’t have the resources or time to do that. But, first, collect and preserve data, then do preliminary analyses within the time limits that we had, make recommendations for additional work where appropriate, and, for those items that we could come to a conclusion on, make recommendations that might improve the performance of buildings in the future.

There were several buildings that were very much of importance to us. Obviously, Buildings 1 and 2, the two towers, were high on our list of buildings to study. Building 3, the Marriott Hotel, which was crushed by the falling debris, was on our list. But we had others—Buildings 4, 5 and 6, that were around the base of the towers, were still partially standing and provided us with insight as to the performance of buildings in fire. Building 7, which was across the street from the main towers, also collapsed and provided us with the first example that we recognized of a building collapsing as a result of fire. Bankers Trust was another building of importance because it stood up and did not collapse as a result of the attack.

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To orient everyone just briefly, the four buildings that collapsed are shown in the center of this slide. They are the four buildings that are not colored. In addition to those, the three red buildings around the base of the towers are Buildings 4, 5, and 6. Bankers Trust is across the street at the bottom of the slide. We also investigated and commented on all of the buildings in blue and yellow on this slide.

To briefly mention how we did some of our work—this is a view looking down upon the World Trade Center site and it shows one of the aircraft as it approached. In this case, it was the aircraft that crashed into Tower 1. We were able to get the information on size of that aircraft. And we also, from the photographs that we had, were able to determine the angle at which that plane hit the building.

Using this information, we were able to go from photographs, such as this, that we enhanced with the help of others, so that we could see the damage to the building. And we were able to come up with information as shown here. This shows the north face of the north tower, Tower 1, and shows where the aircraft plunged into the building, and which of the columns were destroyed or damaged as a result of the crash into the building.

Based upon all the information we were able to gather, we have a number of findings and observations. First of all, the tower sequence of collapse. Clearly, the impact of the aircraft was not enough to bring down either of the two towers. It required a second major event, an event that could have been wind, earthquake, or any of the normal things that we expect will affect buildings. In this case, the second event was the fire.

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The buildings survived for the time that they did—one for almost an hour, the other for substantially more than an hour—because of several items. First of all, there were a large number of columns so that there was a way to transfer the load into other parts of the building after substantial portions of the building were removed by the crash. Then, those columns that were there before the crash had over capacity, so that when the load was transferred to them, they still had enough reserve capacity to carry the additional load.

In Buildings 1 and 2, the impact, we found, did dislodge some of the fireproofing. It also damaged the stair enclosures, thereby blocking five of the six stairwells in the buildings. There were three in each building. We believe all of the stairwells were blocked by the impact in Tower 1 and two of the three were blocked in Tower 2. We know that four people did escape from above the crash level in Building 2 and, therefore, that was the evidence that one stairway was passable, though not in good condition. The collapse occurred from the fire after the very horrendous damage that was done by the aircraft crashing into the two towers.

We have several lessons learned from this. These lessons can be used to improve future construction. For those buildings that are identified as potential targets for terrorists, we have found a need for the redundancy like we saw in these buildings. We need a way to transfer the load into other parts of the building so that they don’t collapse immediately. We also need robustness—that is, the over-strength in parts of the building, so when the load is transferred to them, they have the capacity to take it.

We also need to consider the fire resistance as it is related to the importance of the member that is being protected from the fire. Some parts of the building are more important than other parts and, therefore, need to have different fire resistance.

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For the fireproofing itself, we learned several lessons. Again, these can be applied immediately to those buildings that are potential targets for terrorist attack. For one thing, we found that we need the fireproofing to stick better to the steel. It needs to stick not only under the impact that we might expect in a building that is attacked by terrorists, but also under the deformations that may occur in the parts of the building as the fire heats them up and weakens them. It needs to be effective after the attack.

We have learned lessons about the fire protection for, again, buildings that are possibly terrorist targets. The sprinkler system, the water supply needs to be reliable, and we need redundancy in the system so that if we lose the water from one source, we have another way to supply water. We obviously saw in these buildings that the sprinklers did not work, and that means that we have a reduction in the protection that we have for the buildings.

We learned lessons about exiting the buildings. Again, for buildings that might be the target of terrorists, we need redundancy in the exits. We need more than one way of getting out of a building. We need those exits to be strong enough that they can take the impact that can occur as a result of these attacks, and we need a separation of the exits, one from another, so that if an attack occurs in one part of the building, there is a better chance that the other part of the building, which was not hurt as badly, will have an exit that is operational. Finally, we need impact resistance in the exits.

For connections—we have learned several things about connections, and this can apply to buildings more than just those that might be terrorist targets. First of all, we need to have connections fire-rated. And when I talk about connections, I am talking about the way in which we attach beams to columns and make attachments within the length of a beam, that sort of thing.

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In addition, we need test data. At the moment we do not have the test data to tell us what to do to get the ratings that are appropriate. We also need further analysis to see what the effect is of the types of changes that we might make in future building codes.

One of the major things that we have concluded is that there are several areas that we need additional work on. We did not anticipate that we would answer all of the questions with this study. We did always anticipate that we would point the direction to those things that need further work. We need to complete the analyses that we started in our part of the study.

We also need to develop fire test information. We need to physically test connections under the conditions of fire so that we can determine how to recommend the fire protection of connections.

Another thing is, we need to complete the study of Tower 7. Again, this was the first building we recognized that collapsed as a result of fire alone, without known severe physical damage to the building besides the fire.

Another area which we did not get into in any depth in this study is the human factors: how people reacted to the events, how they exited the buildings, what needs to be done to make it more certain that they will make the right choice in how they try to exit the buildings. That is a large area that does need additional study. And there are a number of other items in our report that we identify as having specific research needs.

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In summary, the towers survived the impacts. It was the fire, in addition to this very severe impact, that finally brought the towers down. They would have stood there indefinitely waiting for the next big event if the fire had not been occurring virtually simultaneously with the effects of the impact.

Redundancy and robustness worked in the towers and it also worked in adjacent buildings, such as Bankers Trust. Major supports in a building need special consideration for fire protection. We believe that it was one of the major supports in Building 7 that started to collapse first and allow the entire building to come down. Fire resistance of connections is an important consideration that is not thoroughly addressed at the moment in the building codes and this needs to be changed.

We need to relate the fireproofing to the fire load. If the loads are increased in an area, then we need to apply appropriate fireproofing in that area. And, finally, egress or exiting with impact needs to be reviewed. The exit ways, such as stairwells, need to be able to survive the impacts that might occur in those buildings that might be subject to terrorist attacks. Thank you, Mr. Chairman.

[The prepared statement of Dr. Corley follows:]

PREPARED STATEMENT OF W. GENE CORLEY

Following the September 11, 2001, attacks on New York City’s World Trade Center, the Federal Emergency Management Agency (FEMA) and the Structural Engineering Institute of the American Society of Civil Engineers (SEI/ASCE), in association with New York City and several other federal agencies and professional organizations, deployed a team of civil, structural, and fire protection engineers to study the performance of buildings at the World Trade Center (WTC) site.

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Founded in 1852, ASCE represents more than 125,000 civil engineers worldwide and is the country’s oldest national engineering society. ASCE members represent the profession most responsible for the nation’s built environment. Our members work in consulting, contracting, industry, government and academia. In addition to developing guideline documents, state-of-the-art reports, and a multitude of different journals, ASCE, an American National Standards Institute (ANSI) approved standards developer, establishes standards of practice such as the document known as ASCE 7 which provides minimum design loads for buildings and other structures. ASCE 7 is used internationally and is referenced in all of our nation’s major model building codes.

The events of following the attacks in New York City were among the worst building disasters and resulted in the largest loss of life from any single building event in the United States. Of the 58,000 people estimated to be at the WTC Complex, over 3,000 lives were lost that day, including 343 emergency responders. Two commercial airliners were hijacked, and each was flown into one of the two 110-story towers. The structural damage sustained by each tower from the impact, combined with the ensuing fires, resulted in the total collapse of each building. As the towers collapsed, massive debris clouds, consisting of crushed and broken building components, fell onto and blew into surrounding structures, causing extensive collateral damage and, in some cases, igniting additional fires and causing additional collapses. In total, 10 major buildings experienced partial or total collapse and 30 million square feet of commercial office space was removed from service, of which 12 million belonged to the WTC complex.

Scope of the study

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The purpose of the FEMA/ASCE was to see what could be learned to make buildings safer in the future. Building performance studies are often done when there is major structural damage due to events such as earthquakes or blasts. A better understanding of how building respond to extreme forces can help us design safer structures in the future.

Specifically, the scope of the FEMA/ASCE study was to:

review damage caused by the attack;

assess how each building performed under the attack;

determine how each building collapsed;

collect and preserve data that may aid in future studies; and

offer guidelines for additional study.

The team examined:

The immediate effects of the aircraft impact on each tower;

The spread of the fire following the crashes;

The reduction in structural strength caused by the fires;

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The chain of events that led to the collapse of the towers; and

How falling debris and the effects of the fires impacted the other buildings at the World Trade Center complex.

The team recommendations are presented for more detailed engineering studies, to complete the assessments and produce improved guidance and tools for building design and performance evaluation.

World Trade Center 1 and World Trade Center 2

As each tower was struck, extensive structural damage, including localized collapse, occurred at the several floor levels directly impacted by the aircraft. Despite this massive localized damage, each structure remained standing. However, as each aircraft impacted a building, jet fuel on board ignited. Part of this fuel immediately burned off in the large fireballs that erupted at the impact floors. Remaining fuel flowed across the floors and down elevator and utility shafts, igniting intense fires throughout upper portions of the buildings. As these fires spread, they further weakened the steel-framed structures, eventually triggering total collapse.

The collapse of the twin towers astonished most observers, including knowledgeable structural engineers, and, in the immediate aftermath, a wide range of explanations were offered in an attempt to help the public understand these tragic and unthinkable events. However, the collapse of these symbolic buildings entailed a complex series of events that were not identical for each tower. To determine the sequence of events, likely root causes, and methods or technologies that may improve or mitigate the building performance observed, FEMA and ASCE formed a Building Performance Study (BPS) Team consisting of specialists in tall building design, steel and connection technology, fire and blast engineering, and structural investigation and analysis.

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The SEI/ASCE team conducted field observations at the WTC site and steel salvage yards, removed and tested samples of the collapsed structures, viewed hundreds of images of video and still photography, conducted interviews with witnesses and persons involved in the design, construction, and maintenance of each of the affected buildings, reviewed available construction documents, and conducted preliminary analyses of the damage to the WTC towers.

With the information and time available, the sequence of events leading to the collapse of each tower could not be definitively determined. However, the following observations and findings were made:

The structural damage sustained by each of the two buildings as a result of the terrorist attacks was massive. The fact that the structures were able to sustain this level of damage and remain standing for an extended period of time is remarkable and is the reason that most building occupants were able to evacuate safely. Events of this type, resulting in such substantial damage, are generally not considered in building design, and the fact that these structures were able to successfully withstand such damage is noteworthy.

Preliminary analyses of the damaged structures, together with the fact the structures remained standing for an extended period of time, suggest that, absent other severe loading events, such as a windstorm or earthquake, the buildings could have remained standing in their damaged states until subjected to some significant additional load. However, the structures were subjected to a second, simultaneous severe loading event in the form of the fires caused by the aircraft impacts.

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The large quantity of jet fuel carried by each aircraft ignited upon impact into each building. A significant portion of this fuel was consumed immediately in the ensuing fireballs. The remaining fuel is believed either to have flowed down through the buildings or to have burned off within a few minutes of the aircraft impact. The heat produced by this burning jet fuel does not by itself appear to have been sufficient to initiate the structural collapses. However, as the burning jet fuel spread across several floors of the buildings, it ignited much of the buildings’ contents, permitting fires to evolve across several floors of the buildings simultaneously. The heat output from these fires is estimated to have been comparable to the power produced by a large commercial generating station. Over a period of many minutes, this heat induced additional stresses into the damaged structural frames while simultaneously softening and weakening these frames. This additional loading and damage were sufficient to induce the collapse of both structures.

The ability of the two towers to withstand aircraft impacts without immediate collapse was a direct function of their design and construction characteristics, as was the vulnerability of the two towers to collapse as a result of the combined effects of the impacts and ensuing fires. Many buildings with other design and construction characteristics would have been more vulnerable to collapse in these events than the two towers, and few may have been less vulnerable. It was not the purpose of this study to assess the code-conformance of the building design and construction, or to judge the adequacy of these features. However, during the course of this study, the structural and fire protection features of the building were examined. The study did not reveal any specific structural features that would be regarded as substandard, and, in fact, many structural and fire protection features of the design and construction were found to be superior to the minimum code requirements.

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What caused the collapse of the towers?

Our analysis showed that the impact alone did not cause the collapse of the towers, but instead, left the towers vulnerable to collapse from any significant additional force, such as from high winds, an earthquake, or in the case of the Twin Towers, the fires that engulfed both buildings. Without that second event, the team believes the towers could have remained standing indefinitely.

Although steel is very strong, it loses some of its strength when heated. To prevent that loss of strength, structural steel is protected with fireproofing and sprinkler systems. In the towers, fires raged throughout several floors simultaneously, ignited by the jet fuel and fed by a mixture of paper and furniture. The impact dislodged some fireproofing on the structural beams and columns, which made them vulnerable to fire damage. With the sprinkler systems disabled, the fires raged uncontrollably, weakening the steel and leading to the collapse of the buildings.

Several building design features have been identified as key to the buildings’ ability to remain standing as long as they did and to allow the evacuation of most building occupants. These included the following:

robustness and redundancy of the steel framing system;

presence of adequate egress stairways that were well marked and lighted; and

the conscientious implementation of emergency exiting training programs for building tenants.

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Similarly, several design features have been identified that may have played a role in allowing the buildings to collapse in the manner that they did and in the inability of victims at and above the impact floors to safely exit. These features should not be regarded either as design deficiencies or as features that should be prohibited in future building codes. Rather, these are features that should be subjected to more detailed evaluation, in order to understand their contribution to the performance of these buildings and how they may perform in other buildings. These include the following:

the type of steel floor truss system present in these buildings and their structural robustness and redundancy when compared to other structural systems;

use of impact-resistant enclosures around egress paths;

resistance of passive fire protection to blasts and impacts in buildings designed to provide resistance to such hazards; and

grouping emergency egress stairways in the central building core as opposed to dispersing them throughout the structure

Building Codes

During the course of this study, the question of whether building codes should be changed in some way to make future buildings more resistant to such attacks was frequently explored. Depending on the size of the aircraft, it may not be technically feasible to develop design provisions that would enable structures to be designed and constructed to resist the effects of impacts by rapidly moving aircraft, and the ensuing fires, without collapse. In addition, the cost of constructing such structures might be so large as to make this type of design intent practically infeasible.

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Although the attacks on the World Trade Center are a reason to question design philosophies, the BPS Team believes there are insufficient data to determine whether there is a reasonable threat of attacks on specific buildings to recommend inclusion of such requirements in building codes. Some believe the likelihood of such attacks on any specific building is deemed sufficiently low to not be considered at all. However, individual building developers may wish to consider design provisions for improving redundancy and robustness for such unforeseen events, particularly for structures that, by nature of their design or occupancy, may be especially susceptible to such incidents. Although some conceptual changes to the building codes that could make buildings more resistant to fire or impact damage or more conducive to occupant egress were identified in the course of this study, the BPS Team felt that extensive technical, policy, and economic study of these concepts should be performed before any specific code change recommendations are developed. This report specifically recommends such additional studies. Future building codes revisions may be considered after the technical details of the collapses and other building responses to damage are better understood.

Surrounding Buildings

Several other buildings, including the Marriott Hotel (WTC 3), the South Plaza building (WTC 4), the U.S. Customs building (WTC 6), and the Winter Garden, experienced nearly total collapse as a result of the massive quantities of debris that fell on them when the two towers collapsed. The St. Nicholas Greek Orthodox Church just south of WTC 2 was completely destroyed by the debris that fell on it.

WTC 5, WTC 7, 90 West Street, 130 Cedar Street, Bankers Trust, the Verizon building, and World Financial Center 3 were impacted by large debris from the collapsing twin towers and suffered structural damage, but arrested collapse to localized areas. The performance of these buildings demonstrates the inherent ability of redundant steel-framed structures to withstand extensive damage from earthquakes, blasts, and other extreme events without progressive collapse.

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The debris from the collapses of the WTC towers also initiated fires in surrounding buildings, including WTC 4, 5, 6, 7; 90 West Street; and 130 Cedar Street. Many of the buildings suffered severe fire damage but remained standing. However, two steel-framed structures experienced fire-induced collapse. WTC 7 collapsed completely after burning unchecked for approximately 7 hours, and a partial collapse occurred in an interior section of WTC 5. Studies of WTC 7 indicate that the collapse began in the lower stories, either through failure of major load transfer members located above an electrical substation structure or in columns in the stories above the transfer structure. The collapse of WTC 7 caused damage to the Verizon building and 30 West Broadway. The partial collapse of WTC 5 was not initiated by debris and is possibly a result of fire-induced connection failures. The collapse of these structures is particularly significant in that, prior to these events, no protected steel-frame structure, the most common form of large commercial construction in the United States, had ever experienced a fire-induced collapse. Thus, these events may highlight new building vulnerabilities, not previously believed to exist.

In the study of the WTC towers and the surrounding buildings that were subsequently damaged by falling debris and fire, several issues were found to be critical to the observed building performance in one or more buildings.

General Observations, Findings and Recommendations

These issues above fall into several broad topics that should be considered for buildings that are being evaluated or designed for extreme events. It may be that some of these issues should be considered for all buildings; however, additional studies are required before general recommendations, if any, can be made for all buildings. The issues identified from this study of damaged buildings in or near the WTC site have been summarized into the following points:

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a. Structural framing systems need redundancy and/or robustness, so that alternative paths or additional capacity is available for transmitting loads when building damage occurs.

b. Fireproofing needs to adhere under impact and fire conditions that deform steel members, so that the coatings remain on the steel and provide the intended protection.

c. Connection performance under impact loads and during fire loads needs to be analytically understood and quantified for improved design capabilities and performance as critical components in structural frames.

d. Fire protection ratings that include the use of sprinklers in buildings require a reliable and redundant water supply. If the water supply is interrupted, the assumed fire protection is greatly reduced.

e. Egress systems currently in use should be evaluated for redundancy and robustness in providing egress when building damage occurs, including the issues of transfer floors, stair spacing and locations, and stairwell enclosure impact resistance.

f. Fire protection ratings and safety factors for structural transfer systems should be evaluated for their adequacy relative to the role of transfer systems in building stability.

What significant recommendations does the team make in its report?

What may be most important is that the BPS Team does not recommend any immediate changes to building codes. The Team believes that there are a number of areas that need further study, and that there are some things that building designers could do to improve safety for occupants in buildings that might be possible terrorist targets.

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In general terms, the FEMA/ASCE report suggests that critical building components such as the structural frame, the sprinkler system or the exit stairwells be designed to be more redundant, more robust, or both. Redundancy means, for example, that if some structural columns were shattered, the building would be designed to transfer the weight to other columns. Robustness means making the builder stronger and better able to resist impact without collapse.

The team is also strongly urging additional study of the collapse of the buildings.

What key findings impact all existing buildings?

The team found that some connections between the structural steel beams failed in the fire. This was most apparent in the collapse of World Trade Center Building 5, where the fireproofing did not protect the connections, causing the structure to fail.

The team is calling for more research and analysis of the how the connections weakened and how best to strengthen their resistance to future fires. Typically, fire resistance tests are limited to steel members, not to the steel connections. Furthermore, fireproofing is sprayed on the connections the same way it is applied to the trusses, though the steel in the trusses and joints may be made of different alloys.

Specific Observations, Findings, and Recommendations

The following sections present observations, findings, and recommendations specifically made in each chapter of the FEMA/ASCE report, including the discussion of building codes and fire standards and the limited metallurgical examination of steel from the WTC towers and WTC 7.

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Building Codes and Fire Standards

Observations and Findings

a. The decision to include aircraft impact as a design parameter for a building would clearly result in a major change in the design, livability, usability, and cost of buildings. In addition, reliably designing a building to survive the impact of the largest aircraft available now or in the future may not be possible. These types of loads and analyses are not suitable for inclusion in minimum loads required for design of all buildings. Just as the possibility of a Boeing 707 impact was a consideration in the original design of WTC 1 and WTC 2, there may be situations where it is desirable to evaluate building survival for impact of an airplane of a specific size traveling at a specific speed. Although there is limited public information available on this topic, interested building owners and design professionals would require further guidance for application to buildings.

b. The ASTM E119 Standard Fire Test was developed as a comparative test, not a predictive one. In effect, the Standard Fire Test is used to evaluate the relative performance (fire endurance) of different construction assemblies under controlled laboratory conditions, not to predict performance in real, uncontrolled fires.

World Trade Center 1 and World Trade Center 2

Observations and Findings

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a. The structural damage sustained by each of the two buildings as aircraft impacted them during the attacks was massive. The fact that the structures were able to sustain this level of damage and remain standing for an extended period of time is remarkable and is the reason that most building occupants were able to evacuate safely. Events of this type, resulting in such substantial damage, are generally not considered in building design, and the ability of these structures to successfully withstand such damage is noteworthy.

b. Preliminary analyses of the damaged structures, together with the fact the structures remained standing for an extended period of time, suggest that absent other severe loading events, such as a windstorm or earthquake, the buildings could have remained standing in their damaged states until subjected to some significant additional load. However, the structures were subjected to a second, simultaneous severe loading event in the form of the fires caused by the aircraft impacts.

c. The large quantity of jet fuel carried by each aircraft ignited upon impact into each building. A significant portion of this fuel was consumed immediately in the ensuing fireballs. The remaining fuel is believed either to have flowed down through the buildings or to have burned off within a few minutes of the aircraft impact. The heat produced by this burning jet fuel does not by itself appear to have been sufficient to initiate the structural collapses. However, as the burning jet fuel spread across several floors of the buildings, it ignited much of the buildings’ contents, permitting fires to evolve across several floors of the buildings simultaneously. The heat output from these fires is estimated to have been comparable to the power produced by a large commercial generating station. Over a period of many minutes, this heat induced additional stresses into the damaged structural frames while simultaneously softening and weakening these frames. This additional loading and damage were sufficient to induce the collapse of both structures.

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d. Because the aircraft impacts into the two buildings are not believed to have been sufficient to cause collapse without the ensuing fires, an obvious question exists as to whether the fires alone, without the damage from the aircraft impact, would have been sufficient to cause such a collapse. The capabilities of the building fire protection systems make it extremely unlikely that such fires could develop without some unusual triggering event like the aircraft impact. For all other cases, the fire protection for the tower buildings provided in-depth protection. The first line of defense was the automatic sprinkler protection. The sprinkler system was intended to respond quickly and automatically to extinguish or confine a fire. The second line of defense consisted of the manual (FDNY/Port Authority Fire Brigade) firefighting capabilities, which were supported by the building standpipe system, emergency fire department use elevators, smoke control system, and other features. Manual suppression by FDNY was the principal fire protection mechanism that controlled a large fire that occurred in the buildings in 1975. Finally, the last line of defense was the structural fire resistance. The fire resistance capabilities would not be called upon unless both the automatic and manual suppression systems previously described failed. In the incident of September 11, not only did the aircraft impact disable the first two lines of defense, they also are believed to have dislodged fireproofing and imposed major additional stresses on the structural system.

e. Had some other event defeated both the automatic and manual suppression capabilities and a fire of major proportions occurred while the structural framing system and its fireproofing remained intact, the third line of defense, structural fireproofing, would have become critical. The thickness and quality of the fireproofing materials would have been key factors in the rate and extent of temperature rise in the floor trusses and other structural members. In the preparation of this report, there has not been sufficient analysis to predict the temperature and resulting change in strength of the individual structural members in order to approximate the overall response of the structure. Given the redundancy in the framing system and the capability of that system to redistribute load from a weakened member to other parts of the structural system, it is impossible without extensive modeling and other analysis to make a credible prediction of how the building would have responded to an extremely severe fire in a situation where there was no prior structural damage. Such simulations have not been performed within the scope of this study, but should be performed in the future.

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f. Buildings are designed to withstand loading events that are deemed credible hazards and to protect the public safety in the event such credible hazards are experienced. Buildings are not designed to withstand any event that could ever conceivably occur, and any building can collapse if subjected to a sufficiently extreme loading event. Communities adopt building codes to help building designers and regulators determine those loading events that should be considered as credible hazards in the design process. These building codes are developed by the design and regulation communities themselves, through a voluntary committee consensus process. Prior to September 11, 2001, it was the consensus of these communities that aircraft impact was not a sufficiently credible hazard to warrant routine consideration in the design of buildings and, therefore, the building codes did not require that such events be considered in building design. Nevertheless, design of WTC 1 and WTC 2 did include at least some consideration of the probable response of the buildings to an aircraft impact, albeit a somewhat smaller and slower moving aircraft than those actually involved in the September 11 events. Building codes do regard fire as a credible hazard and include extensive requirements to control the spread of fire throughout buildings, to delay the onset of fire-induced structural collapse, and to facilitate the safe egress of building occupants in a fire event. For fire-protected steel-frame buildings, like WTC 1 and WTC 2, these code requirements had been deemed effective and, in fact, prior to September 11, there was no record of the fire-induced-collapse of such structures, despite some very large uncontrolled fires.

g. The ability of the two towers to withstand aircraft impacts without immediate collapse was a direct function of their design and construction characteristics, as was the vulnerability of the two towers to collapse as a result of the combined effects of the impacts and ensuing fires. Many buildings with other design and construction characteristics would have been more vulnerable to collapse in these events than the two towers, and few may have been less vulnerable. It was not the purpose of this study to assess the code-conformance of the building design and construction, or to judge the adequacy of these features. However, during the course of this study, the structural and fire protection features of the building were examined. The study did not reveal any specific structural features that would be regarded as substandard, and, in fact, many structural and fire protection features of the design and construction were found to be superior to the minimum code requirements.

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h. Several building design features have been identified as key to the buildings’ ability to remain standing as long as they did and to allow the evacuation of most building occupants. These include the following:

robustness and redundancy of the steel framing system;

presence of adequate egress stairways that were; and

the conscientious implementation of emergency exiting training programs for building tenants.

i. Similarly, several design features have been identified that may have played a role in allowing the buildings to collapse in the manner that they did and in the inability of victims at and above the impact floors to safely exit. These features should not be regarded either as design deficiencies or as features that should be prohibited in future building codes. Rather, these are features that should be subjected to more detailed evaluation, in order to understand their contribution to the performance of these buildings and how they may perform in other buildings. These include the following:

the type of steel floor truss system present in these buildings and their structural robustness and redundancy when compared to other structural systems;

use of impact-resistant enclosures around egress paths;

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resistance of passive fire protection to blasts and impacts in buildings designed to provide resistance to such hazards; and

grouping emergency egress stairways in the central building core, as opposed to dispersing them throughout the structure.

j. During the course of this study, the question of whether building codes should be changed in some way to make future buildings more resistant to such attacks was frequently explored. Depending on the size of the aircraft, it may not be technically feasible to develop design provisions that would enable structures to be designed and constructed to resist the effects of impacts by rapidly moving aircraft, and the ensuing fires, without collapse. In addition, the cost of constructing such structures might be so large as to make this type of design intent practically infeasible.

Although the attacks on the World Trade Center are a reason to question design philosophies, the BPS Team believes there are insufficient data to determine whether there is a reasonable threat of attacks on specific buildings to recommend inclusion of such requirements in building codes. Some believe the likelihood of such attacks on any specific building is deemed sufficiently low to not be considered at all. However, individual building developers may wish to consider design provisions for improving redundancy and robustness for such unforeseen events, particularly for structures that, by nature of their design or occupancy, may be especially susceptible to such incidents. Although some conceptual changes to the building codes that could make buildings more resistant to fire or impact damage or more conducive to occupant egress were identified in the course of this study, the BPS Team felt that extensive technical, policy, and economic study of these concepts should be performed before any specific code change recommendations are developed. This report specifically recommends such additional studies. Future building codes revisions may be considered after the technical details of the collapses and other building responses to damage are better understood.

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Recommendations

The scope of this study was not intended to include in-depth analysis of many issues that should be explored before final conclusions are reached. Additional studies of the performance of WTC 1 and WTC 2 during the events of September 11, 2001, and of related building performance issues should be conducted. These include the following:

a. During the course of this study, it was not possible to determine the condition of the interior structure of the two towers, after aircraft impact and before collapse. Detailed modeling of the aircraft impacts into the buildings should be conducted in order to provide understanding of the probable damage state immediately following the impacts.

b. Preliminary studies of the growth and heat flux produced by the fires were conducted. Although these studies provided useful insight into the buildings’ behavior, they were not of sufficient detail to permit an understanding of the probable distribution of temperatures in the buildings at various stages of the event and the resulting stress state of the structures as the fires progressed. Detailed modeling of the fires should be continued and should be combined with structural modeling to develop specific failure modes likely to have occurred.

c. The floor framing system for the two towers was very complex and substantially more redundant than typical bar joist floor systems. Detailed modeling of these floor systems and their connections should be conducted to understand the effects of localized overloads and failures to determine ultimate failure modes. Other types of common building framing should also be examined for these effects.

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d. The fire-performance of steel trusses with spray-applied fire protection, and with end restraint conditions similar to that present in the two towers, is not well understood, but is likely critical to the building collapse. Studies of the fire-performance of this structural system should be conducted.

e. Observations of the debris generated by the collapse and of damaged adjacent structures suggests that spray-applied fireproofing may be vulnerable to mechanical damage from blasts and impacts. This vulnerability is not well understood. Tests of these materials should be conducted to understand how well they withstand such mechanical damage and to determine whether it is appropriate and feasible to improve their resistance to such damage.

f. In the past, tall buildings have occasionally been damaged, typically by earthquakes, and experienced collapse within the damaged zones. Those structures were able to arrest collapse before they progressed to a state of total collapse. The two WTC towers were able to arrest collapse from the impact damage but not from the resulting fire when combined with the impact effects of the aircraft attack. Studies should be conducted to determine, given the great size and weight of the two towers, whether there are feasible design and construction features that would permit such buildings to arrest or limit a collapse, once it began.

World Trade Center 3

Observations

WTC 3 was subjected to extraordinary loading from the impact and weight of debris from the two adjacent 110-story towers. It is noteworthy that the building resisted both horizontal and vertical progressive collapse after the collapse of WTC 2. The overloaded portions were able to break away from the rest of the structure without pulling it down and the remaining structural system was able to remain stable and support the debris load. The structure was even capable of protecting occupants after the collapse of WTC 1.

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Recommendations

WTC 3 should be studied further to understand how it resisted progressive collapse.

World Trade Center 7

Observations and Findings

a. This office building was built over an electrical substation and a power plant, comparable in size to that operated by a small commercial utility. It also had a significant amount of diesel oil storage and had a structural system with numerous horizontal transfers for gravity and lateral loads.

b. The loss of the east penthouse on the videotape records suggests that the collapse event was initiated by the loss of structural integrity in one of the transfer systems. Loss of structural integrity was likely a result of weakening caused by fires on the 5th to 7th floors. The specifics of the fires in WTC 7 and how they caused the building to collapse remain unknown at this time. Although the total diesel fuel on the premises contained massive potential energy, the best hypothesis has only a low probability of occurrence. Further research, investigation, and analyses are needed to resolve this issue.

c. The collapse of WTC 7 was different from that of WTC 1 and WTC 2. The towers showered debris in a wide radius as their external frames essentially ”peeled” outward and fell from the top to the bottom. In contrast, the collapse of WTC 7 had a relatively small debris field because the facade came straight down, suggesting an internal collapse. Review of video footage indicates that the collapse began at the lower floors on the east side. Studies of WTC 7 indicate that the collapse began in the lower stories, either through failure of major load transfer members located above an electrical substation structure or in columns in the stories above the transfer structure. Loss of strength due to the transfer trusses could explain why the building imploded, with collapse initiating at an interior location. The collapse may have then spread to the west, causing interior members to continue collapsing. The building at this point may have had extensive interior structural failures that then led to the collapse of the overall building, including the cantilever transfer girders along the north elevation, the strong diaphragms at the 5th and 7th floors, and the seat connections between the interior beams and columns at the building perimeter.

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Recommendations

The scope of this study was not intended to include in-depth analysis of issues. Certain issues should be explored before final conclusions are reached and additional studies of the performance of the WTC 7 building and related building performance issues should be conducted. These include the following:

a. Additional data should be collected to confirm the extent of the damage to the south face of the building caused by falling debris.

b. Determination of the specific fuel loads, especially at the lower levels, is important to identify possible fuel supplied to sustain the fires for a substantial duration. Areas of interest include storage rooms, file rooms, spaces with high-density combustible materials, and locations of fuel lines. The control and operation of the emergency power system, including generators and storage tanks, needs to be thoroughly understood. Specifically, the ability of the diesel fuel pumps to continue to operate and send fuel to the upper floors after a fuel line is severed should be confirmed.

c. Modeling and analysis of the interaction between the fire and structure are important. Specifically, the anticipated temperatures and duration of the fires and the effects of the fires on the structure need to be examined with an emphasis on the behavior of transfer systems and their connections.

d. Suggested mechanisms for a progressive collapse should be studied and confirmed. How the collapse of an unknown number of gravity columns brought down the whole building should be explained.

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e. The role of the axial capacity between the beam-column connection and the relatively strong structural diaphragms may have had in the progressive collapse should be explained.

f. The level of fire resistance and the ratio of capacity-to-demand required for structural members and connection deemed to be critical to the performance of the building should be studied. The collapse of some structural members and connections may be more detrimental to the overall performance of the building than other structural members. The adequacy of current design provisions for members whose failure could result in large-scale collapse should also be studied.

Recommendations for Future Study

The Building Performance Study Team has developed recommendations for specific issues, based on the study of the performance of the WTC towers and surrounding buildings in response to the impact and fire damage that occurred. These recommendations have a broader scope than the important issue of building concepts and design for mitigating damage from terrorist attacks, and also address the level at which resources should be expended for aircraft security, how the fire protection and structural engineering communities should increase their interaction in building design and construction, possible considerations for improved egress in damaged structures, the public understanding of typical building design capacities, issues related to the study process and future activities, and issues for communities to consider if they are developing emergency response plans that include engineering response.

National Response. Resources should be directed primarily to aviation and other security measures rather than to hardening buildings against airplane impact. The relationship and cooperation between public and private organizations should be evaluated to determine the most effective mechanisms and approaches in the response of the nation to such disasters.

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Interaction of Structural Elements and Fire. The existing prescriptive fire resistance rating method (ASTM E119) does not provide sufficient information to determine how long a building component can be expected to perform in an actual fire. A method of assessing performance of structural members and connections as part of a structural system in building fires is needed for designers and emergency personnel.

The behavior of the structural system under fire conditions should be considered as an integral part of the structural design. Recommendations are to:

Develop design tools, including an integrated model that predicts heating conditions produced by the fire, temperature rise of the structural component, and structural response.

Provide interdisciplinary training in structures and fire protection for both structural engineers and fire protection engineers.

Performance criteria and test methods of fireproofing materials relative to their durability, adhesion, and cohesion when exposed to abrasion, shock, vibration, rapid temperature rise, and high temperature exposures need further study.

Interaction of Structural and Fire Professionals in Design. The structural, mechanical, architectural, fire protection, blast, explosion, earthquake, and wind engineering communities need to work together to develop guidance for vulnerability assessment, retrofit, and design of concrete and steel structures to mitigate or reduce the probability of progressive collapse under single- and multiple-hazard scenarios.

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An improved level of interaction between structural and fire protection engineers is encouraged. Specific recommendations are to:

Consider behavior of the structural system under fire as an integral part of the design process.

Provide cross-training of fire protection and structural engineers in the performance of structures and building fires.

Fire Protection and Engineering Discipline. The continued development of a system for performance-based design is encouraged. This involves the following:

Improve the existing models that simulate fire and spread in structures, as well as the impact of fire and smoke on structures and people.

Improve the database on material burning behavior.

Building Evacuation. The following topics were not explicitly examined during this study, but are recognized as important aspects of designing buildings for impact and fire events. Recommendations for further study are to:

Perform an analysis of occupant behavior during evacuation of the buildings at WTC to improve the design of fire alarm and egress systems in high-rise buildings.

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Perform an analysis of the design basis of evacuation systems in high-rise buildings to assess the adequacy of the current design practice, which relies on phased evacuation.

Evaluate the use of elevators as part of the means of egress for mobility impaired people as well as the general building population for the evacuation of high-rise buildings. In addition, the use of elevators for access by emergency personnel needs to be evaluated.

Emergency Personnel. One of the most serious dangers firefighters and other emergency responders face is partial or total collapse of buildings. Recommended steps to provide better protection to emergency personnel are:

Have fire protection and structural engineers assist emergency personnel in developing broader pre-plans for buildings and structures to include more detailed assessments of hazards and response of structural elements and performance of buildings during fires, including identification of critical structural elements.

Develop training materials and courses for emergency personnel with regards to effects of fire on steel.

Review collaboration efforts between the emergency personnel and engineering professions so that engineers may assist emergency personnel in assessments during the time of the incident.

Education of Stakeholders. Stakeholders (e.g., owners, operators, tenants, authorities, designers) should be further educated about building codes, the minimum design loads typically addressed for building design, and the extreme events that are not addressed by building codes. Should stakeholders desire to address events not addressed by the building codes, they should have a basic understanding of developing and implementing strategies to mitigate damage from extreme events.

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Stakeholders should also be educated about the expected performance of their building when renovations, or changes in use or occupancy, occur and the building is subjected to different floor or fire loads. For instance, if the occupancy in a building changes to one with a higher fire hazard, they should review the fire protection systems to ensure there is adequate fire protection. Or, if the structural load is increased with a new occupancy, the structural support system should be reviewed to ensure it can carry the new load.

Study Process. The report benefited from a tremendous amount of professional volunteerism due to the unprecedented level of national disaster. Improvements can be made that would aid the process for any future efforts. Recommendations are to:

Provide resources that are proportional to the required level of effort.

Provide better access to data, including building information, interviews, samples, site photos, and documentation.

Archival Information. Archival information has been collected and provides the groundwork for continued study. It is recommended that a coordinated effort for the preservation of this and other relevant information be undertaken by a responsible organization or agency, capable of maintaining and managing such information. This effort would include:

cataloging all photographic data collected to date;

enhancing video data collected for both quality and timeline;

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conducting interviews with building occupants, witnesses, rescue workers and any others that may provide valuable information; and

initiating public requests for information.

Conclusion

ASCE is proud of the work done by the BPS Team, but strongly believes that the follow up studies recommended by the FEMA/ASCE Report are critical to obtaining the technical knowledge needed by engineers for future building design.

Thank you for the opportunity to express ASCE’s views. We offer you and all of the agencies involved in the recovery efforts ASCE’s full resources to manage the nation’s critical infrastructure needs. We are ready to help in any way possible, and are eager to hear from you regarding ways that ASCE’s Critical Infrastructure Response Initiative can support you as you examine our infrastructure needs in the coming months.

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Chairman BOEHLERT. Thank you very much, Dr. Corley. Dr. Bement.

STATEMENT OF DR. ARDEN L. BEMENT, JR., DIRECTOR, NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY, U.S. DEPARTMENT OF COMMERCE

Dr. BEMENT. Thank you, Mr. Chairman, Mr. Hall, and, members of the Committee. I want to thank you for this opportunity to testify on the NIST proposed investigation into the collapse of the World Trade Center buildings.

I will outline the proposed NIST response plan and show how it complements and is responsive to the efforts of the FEMA/ASCE Building Performance Assessment Team. I commend Dr. Corley and the BPAT members for their report and detailed recommendations.

The NIST proposed response plan consists of three key program elements, including an investigation to be conducted in parallel with, first, a 24-month building and fire safety investigation into the collapse of the Twin Towers and World Trade Center Building 7. The goal here is to investigate the building construction, the materials used, and the technical conditions that combined to cause these disasters following the initial impact of the aircraft. While World Trade Center Buildings 4, 5, and 6 will not be investigated specifically in this phase, what we will learn in examining Buildings 1, 2, and 7 will benefit buildings of all designs.

The second in our response plan is a multi-year research and development program to provide the technical basis to support improved building and fire codes, standards, and practices. This addresses work in critical areas such as structural fire safety, prevention of progressive collapse, and equipment standards for first responders. It includes BPAT recommendations for World Trade Center Buildings 3, 4, 5, and 6, Bankers Trust, and peripheral buildings, as well as recommendations for future studies to address specific issues of broader scope not covered by the BPAT report. Outputs and recommendations will support the voluntary consensus process that is used to develop building and fire codes and standards in the United States.

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The third element of this response plan is an industry-led dissemination and technical assistance program that will provide practical guidance and tools to better prepare facility owners, contractors, designers, and emergency personnel to respond to future disasters. This addresses BPAT recommendations for the training and education of stakeholders.

All of the BPAT recommendations can be seen to map into the three elements of the response plan. We have shared the overall response plan approach extensively with public and private sector organizations and have welcomed their inputs since the middle of October 2001.

Now, let me stop here parenthetically to describe this graphic. This shows generally, or generically, the various recommendations in the BPAT report, and the items that are shown in white will be included in the investigation. The items in yellow will be the focus of the research and development phase of the program, and the items shown in blue will be addressed during the dissemination and technical assistance phase of the response program.(see footnote 1)

Our overall plan was modified in January 2002 when FEMA requested NIST to initiate an investigation under NIST’s unique legislative authorities to conduct structural and fire investigations. This request was in direct response to a growing demand for a broad-based, Federal investigation into the World Trade Center disaster from technical experts, industry leaders, and families of building occupants and first responders who lost their lives on September 11, 2001.

We continue to revise the plan as more technical information becomes available, and to be responsive to the suggestions and needs of these many stakeholders. We agree with the BPAT recommendations that additional study of the Twin Towers and World Trade Center Building 7 should be conducted. The NIST investigation will focus on these buildings. We believe strongly that the results of such an investigation could lead to major changes in both U.S. building and fire codes and in engineering practice. We also believe strongly that the lessons to be derived from such an investigation will be applicable to a broad range of building types, not just the specific buildings that are studied.

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Let me now give you some specific examples to illustrate why we believe this to be the case. These building disasters provide a unique source of information to study the safety and performance of open-web steel trussed joists under fires. This type of trussed joist is used widely in floor and roof systems for commercial and institutional buildings nationwide.

New mechanisms, not considered previously, can be studied that could initiate progressive collapse in buildings as a result of fires and impact loads, including the critical role of pivotal components such as transfer girders and floor diaphragms.

In addition, the mechanical and metallurgical behavior of many different grades of structural steel under fires, using steel recovered from the World Trade Center site, that is now being stored at NIST, can also be investigated.

There are equally important lessons for life safety. First of all, are fire fighting technologies and practices for tall buildings, including occupant behavior, evacuation, emergency response, and the performance of built-in fire protection systems, such as sprinklers and fire alarms. Also, is the control of fire spread in buildings with large, open floor spaces, and the effectiveness in compartmentalization as a means to isolate fires in such buildings.

There are also important lessons to be learned for engineering practice, such as the performance of the design, construction, and approval process used to ensure safety whenever an innovation structural system is used or where there is a need for variances from building and fire codes.

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The provision of adequate structural reserve capacity to accommodate abnormal loads, such as blasts, impact, and accidental fires, especially those that can be anticipated prior to construction, balanced properly against the need to achieve design efficiency is also important.

The proposed NIST investigation will include world-class technical expertise from both within and outside of NIST. External experts will be drawn from both academia and practice, and several of those may well have contributed to the BPAT study. We propose to charter a Federal Advisory Committee to guide all aspects of the NIST investigation, including the review of major investigation reports.

We will maintain ongoing liaison with the professional communities over the course of the investigation through periodic briefings, presentations, and opportunities for comment on key investigation reports.

NIST will assign a special liaison to interact with the families of building occupants and first responders. We recognize the vital role that these individuals and groups have to play in providing input on the scope of the proposed NIST investigation. We also understand that it is appropriate and important to keep these families and organizations informed about the progress of the proposed investigation.

A summary of the proposed NIST investigation plan is attached for the record and is being made available to the general public on the NIST website beginning today. NIST will use an open and inclusive process in planning and conducting the investigation and in publishing its findings and recommendations.(see footnote 2)

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We have and are consulting extensively with technical experts and groups in developing our plan. We have consulted with local authorities in New York who have expressed support for NIST and agreed to cooperate in its investigation. We will hold a public meeting in New York City in the near future to share the details of the proposed NIST plan which will be made available in detail for the general public two weeks prior to the meeting, and will seek the public’s informed comment on its scope and each of the elements as we make the plan final.

The Administration has expressed strong commitment for the NIST response plan and has requested $16 million as part of the FEMA’s fiscal year 2002 supplemental budget request to support the NIST investigation. The President’s fiscal year 2003 budget request also includes $2 million in base funding to support other elements of the NIST response plan. And we have already redirected approximately $2 million of existing base funds within our Building and Fire Research Laboratory to support the response plan. Future resource requirements for the broader research and development and dissemination and technical assistance program will be included in our fiscal year 2004 budget process and beyond.

Finally, Mr. Chairman, I look forward to working with you and members of this Committee as NIST embarks on a very important technical investigation. FEMA and NIST are committed to ensuring a smooth transition. Mr. Robert Shea and I recently signed a Memorandum of Understanding to strengthen our collaborative bonds by designating NIST to serve as a research and technical resource for FEMA. With your permission, I would like to submit a copy of that Memorandum of Understanding for the record.(see footnote 3)

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Chairman BOEHLERT. Without objection, so ordered.

Dr. BEMENT. We have agreed to develop and sign, by the end of May, an operational protocol for a quick deployment mechanism that could be activated when a NIST response to extreme events is needed.

This concludes my prepared written remarks, and I will be glad to answer any questions from the Committee.

[The prepared statement of Dr. Bement follows:]

PREPARED STATEMENT OF ARDEN L. BEMENT, JR.

Chairman Boehlert, Ranking Member Hall, and Members of the Committee, I want to thank you for this opportunity to testify on the National Institute of Standards and Technology’s proposed investigation into the collapse of the World Trade Center (WTC) buildings.

I will outline the proposed NIST response plan today, and show how it complements and is responsive to the efforts of the Building Performance Assessment Team, or BPAT, led by the American Society of Civil Engineers (ASCE) and sponsored by the Federal Emergency Management Agency, FEMA. The response plan addresses all major recommendations contained in the BPAT report. I commend Dr. Gene Corley and the BPAT members for their excellent report and detailed recommendations. The National Institute of Standards and Technology (NIST) has also identified other critical issues that need study, especially in areas that impact life safety and engineering practice.

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The NIST proposed response plan consists of three key program elements—including an investigation—to be conducted in parallel (graphic to be projected on video monitors). These are:

First, a 24-month building and fire safety investigation into the collapse of the Twin Towers (WTC 1 and 2) and WTC 7. The goal of this program element is to investigate the building construction, the materials used, and the technical conditions that combined to cause these disasters following the initial impact of the aircraft. While WTC 4, 5,and 6 will not be investigated specifically in this phase, what we learn in examining WTC 1, 2 and 7 would benefit buildings of all designs.

Second, a multi-year research and development (R&D) program to provide the technical basis to support improved building and fire codes, standards, and practices. This program element addresses work in critical areas such as structural fire safety, prevention of progressive collapse, and equipment standards for first responders. It includes BPAT recommendations for WTC 3, 4, 5, and 6, Bankers Trust, and peripheral buildings as well as recommendations for future studies to address specific issues of broader scope not covered by the BPAT. The program outputs and recommendations will support the voluntary consensus process that is used to develop building and fire codes and standards in the United States.

Third, an industry-led dissemination and technical assistance program (DTAP) that will provide practical guidance and tools to better prepare facility owners, contractors, designers, and emergency personnel to respond to future disasters. The DTAP will also be an important complement to the R&D effort to demonstrate and gain acceptance of proposed changes to practice, standards, and codes. This program element addresses BPAT recommendations for the training and education of stakeholders.

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All the BPAT recommendations can be seen to map into the three above elements in this graphic (graphic on screen).

We have shared the overall response plan approach extensively with public and private sector organizations and have welcomed their inputs since the middle of October 2001. The plan was modified in January 2002 when FEMA requested NIST to initiate an investigation under NIST’s unique legislative authorities to conduct structural and fire investigations. This request was in direct response to a growing demand for a broad-based federal investigation into the World Trade Center disaster from technical experts, industry leaders, and families of building occupants and first responders who lost their lives on September 11, 2001. We continue to revise the plan as more technical information becomes available and to be responsive to the suggestions and needs of these many stakeholders.

The Commerce Department and NIST have received letters supporting our proposed response plan from key industry leaders responsible for U.S. building and fire standards, codes, and practices, including the American Society of Civil Engineers, the National Fire Protection Association, the American Institute of Architects, the Council on Tall Buildings and Urban Habitat, the Construction Industry Institute, the Society of Fire Protection Engineers, and the International Association of Fire Chiefs.

We agree with the BPAT recommendations that additional study of the Twin Towers and WTC 7 should be conducted. The NIST investigation will focus on these buildings. We believe strongly that the results of such an investigation could lead to major changes in both U.S. building and fire codes and in engineering practice, despite the unique design features or circumstances under which the buildings collapsed. We also believe strongly that the lessons to be derived from such an investigation will be applicable to a broad range of buildings types, not just the specific buildings that are studied. Let me now give you some examples to illustrate why we believe this to be the case.

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The Twin Towers and WTC 7 are the only known cases of total structural collapse where fires played a significant role. These disasters provide a unique source of information to understand the complexities associated with the dynamics of real building fires and the collapse vulnerability of buildings to fires. We expect to analyze that information to validate generally applicable methodologies for use in fire safety design and retrofit of structures, and to evaluate the performance of fireproofing materials and connections used in steel structures.

In addition, these building disasters provide a unique source of information to study:

The safety and performance of open-web steel trussed joists under fires. This type of trussed joist is used widely in floor and roof systems for commercial and institutional buildings nationwide.

New mechanisms—not considered previously—that could initiate progressive collapse in buildings as a result of fires and impact loads, including the critical role of pivotal components such as transfer girders and floor diaphragms.

The mechanical and metallurgical behavior of many different grades of structural steel under fires using steel recovered from the WTC site that is being stored at NIST.

There are equally important lessons for life safety—which were outside the scope of the BPAT study:

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Firefighting technologies and practices for tall buildings, including occupant behavior, evacuation, emergency response, and the performance of built-in fire protection systems such as sprinklers and fire alarms.

The control of fire spread in buildings with large open floor plans, and the effectiveness of compartmentation as a means to isolate fires in such buildings.

There are also important lessons to be learned for engineering practice—areas that were not the focus of the BPAT study:

The performance of the design, construction, and approval processes used to assure safety whenever an innovative structural system is used or there is a need for variances from building and fire codes.

The provision of adequate structural reserve capacity to accommodate abnormal loads such as blast, impact, and accidental fires—especially those that can be anticipated prior to construction—balanced properly against the need to achieve design efficiency.

The proposed NIST investigation will include world-class technical expertise from both within and outside NIST. External experts will be drawn from both academia and practice and several of those may well have contributed to the BPAT study.

We propose to charter a Federal Advisory Committee to guide all aspects of the NIST investigation, including the review of major investigation reports. Members of this group will be recognized for their distinguished professional service, possess broad technical expertise and experience, and have a reputation for independence, objectivity, and impartiality.

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I have appointed a Secretariat within NIST to coordinate NIST-level activities in support of the WTC investigation and to maintain ongoing liaison with members of Congress, the public, and the media.

NIST will assign a special liaison to interact with the families of building occupants and first responders. We recognize the vital role that those individuals and groups have to play in providing input on the scope of the proposed NIST investigation. We also understand that it is appropriate and important to keep these families and organizations informed about the progress of the proposed investigation.

We will maintain ongoing liaison with the professional communities over the course of the investigation through periodic briefings, presentations, and opportunity for comment on key investigation reports.

A summary of the proposed NIST investigation plan is attached for the record and is being made available to the general public on the NIST website beginning today. NIST will use an open and inclusive process in planning and conducting the investigation, and in publishing its findings and recommendations. We consulted extensively with technical experts and groups in developing the plan and briefed the BPAT experts at their January 2002 meeting, and again last Wednesday. Yesterday, we briefed representatives of the parent organizations comprising the BPAT coalition. We will hold a public meeting in New York City in the near future to share the details of the proposed NIST plan, which will be made available to the general public two weeks prior, and seek the public’s informed comment on its scope before we adopt the plan as final.

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Following our statutory requirements, before we begin a building investigation, we consult with local authorities. In this case, we consulted with local authorities in New York, including the Port Authority of New York and New Jersey, the Mayor’s Office of Emergency Management, the New York City Department of Design and Construction, and the Fire Department of New York. These organizations have expressed written support for NIST and agreed to cooperate in its investigation.

The Administration has expressed strong commitment for the NIST response plan and has requested $16 million as part of the Federal Emergency Management Agency’s FY 2002 supplemental budget request—now in Congress—to support the NIST investigation. The President’s FY 2003 budget request to Congress also requests an increase of $2 million in base funding to support other elements of the NIST response plan. The Building and Fire Research Laboratory within NIST has already redirected approximately $2 million of its existing base funds to support the response plan. Future resource requirements for the broader research and development and dissemination and technical assistance program will be considered in the Fiscal Year 2004 budget process and beyond.

Finally, Mr. Chairman, I look forward to working with you and members of this Committee as NIST embarks on a very important technical investigation. FEMA and NIST are committed to ensuring a smooth transition. Mr. Robert Shea and I recently signed a Memorandum of Understanding to strengthen our collaborative bonds by designating NIST to serve as a research and technical resource for FEMA. With your permission, I would like to submit a copy of that MOU for the record. We have agreed to develop and sign, by the end of May 2002, an operational protocol for a quick deployment mechanism that could be activated when a NIST response to extreme events is needed.

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This concludes my prepared remarks. I will be pleased to answer your questions.

[The attachments to Dr. Bement’s statement follow:]

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Next Hearing Segment(2)

(Footnote 1 return)
Please refer to Slide 2 of Dr. Bement’s written statement; see p. 82.

(Footnote 2 return)
The summary follows the written statement of Dr. Bement; see p. 54.

(Footnote 3 return)
The MOU follows the written statement of Dr. Bement; see p. 84.

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