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Commerce's NIST Details Federal Investigation of World Trade Center Collapse

More information on the investigation is available at

The Commerce Department's National Institute of Standards and Technology (NIST) today announced details of its $16 million, 24-month federal building and fire safety investigation to study the structural failure and subsequent progressive collapse of several World Trade Center (WTC) buildings following the terrorist attacks of Sept. 11, 2001, in New York City. The study of WTC Buildings 1 and 2 ("The Twin Towers") and WTC Building 7 will focus on the building construction, the materials used and all of the technical conditions that contributed to the outcome of the WTC disaster.

NIST already has completed much of the planning work for the investigation and has consulted extensively with the public concerning its scope. Recent passage of an emergency supplemental appropriations bill now enables NIST to move ahead with the study.

"Many people, including technical experts, industry leaders and families of victims, have pressed for a broad-based federal investigation of the building collapses at the World Trade Center," said NIST Director Arden Bement Jr. "The lessons to be learned from this investigation and the companion research and development program are critical to understanding what core reforms are needed to make tall buildings safer nationwide, enhancing the safety of fire and emergency responders, better protecting occupants and property, and providing better emergency response capabilities and procedures for future disasters."

NIST has extensive experience and expertise in conducting disaster investigations following structural/construction failures, fires and natural disasters, including earthquakes, hurricanes and tornadoes. A fact sheet detailing this background and listing past NIST investigations is available online at

NIST consulted with local authorities in New York about the agency's plans for the WTC investigation, including the following organizations: the Port Authority of New York and New Jersey, the Fire Department of New York, the New York City Department of Buildings, the New York City Department of Design and Construction, and the New York City Office of Emergency Management. A public meeting to gather input on the scope of the pending investigation was held in New York City on June 24, 2002; the suggestions and comments were considered in developing the final investigation plan.

The NIST investigation will involve the participation of world-class technical experts from industry, academia and other laboratories to complement the agency's in-house technical expertise. NIST also will draw expertise from a private-sector coalition that includes professionals from the Structural Engineering Institute of the American Society of Civil Engineers (SEI/ASCE), Society of Fire Protection Engineers (SFPE), the National Fire Protection Association (NFPA), the American Institute of Steel Construction (AISC), the Council on Tall Buildings and Urban Habitat (CTBUH), and the Structural Engineers Association of New York (SEAoNY).

Additionally, NIST will maintain liaison with other industry organizations, standards and codes bodies, and the insurance industry during its investigation, as well as the families of building occupants and first responders, and organizations representing families of victims such as the Skyscraper Safety Campaign.

NIST will charter an advisory committee to provide advice to the NIST Director on all aspects of the investigation and ensure its successful completion. Members of the committee will be recognized for distinguished professional service, possess broad technical expertise and experience, and have a reputation for independence, objectivity and impartiality.

NIST expects to complete its investigation and issue a final report within an estimated 24 months from the start of the program. The investigation is part of a broader NIST response plan to the WTC disaster. In addition to the investigation, NIST is planning to conduct two related programs concurrently:

a multiyear research and development program to provide the technical basis for improved building and fire codes, standards and practices; and

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.

As a non-regulatory agency of the U.S. Department of Commerce's Technology Administration, NIST develops and promotes measurements, standards and technology to enhance productivity, facilitate trade and improve the quality of life.

NOTE: A question-and-answer fact sheet on the investigation is available.

Released August 21, 2002, Updated January 7, 2021