Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

WTC Report Urges Action for Safer Tall Buildings

Testifying before a hearing of the House Science Committee on Oct. 26, National Institute of Standards and Technology (NIST) Director William Jeffrey urged implementation of 30 specific recommendations from the agency's completed investigation of the collapse of the World Trade Center (WTC) towers following the terrorist attacks of Sept. 11, 2001. Jeffrey called on organizations that develop building and fire safety codes, standards and practices—and the state and local agencies that adopt them—to give "immediate and serious consideration" to implementation efforts.

The final investigation report was released at the hearing and is available at

Jeffrey said that NIST believes its recommendations are realistic, appropriate and achievable within a reasonable period of time. However, he cautioned that improvements would only be realized if they are acted upon by the appropriate organizations. To facilitate this effort, NIST to date has:

  • identified specific codes, standards and practices affected by each of the 30 recommendations in the final WTC towers report;
  • reached out to the organizations responsible for making changes to expedite consideration of and action on the recommendations (for example, NIST held a major technical conference on the recommendations in September 2005 attended by more than 200 people, including representatives from all major standards and codes development organizations); and
  • awarded a contract to the non-profit National Institute of Building Sciences to turn many of the recommendations into code language suitable for submission of code change proposals to the two national model code developers, the National Fire Protection Association and the International Code Council.

The NIST recommendations released on Oct. 26 are contained within 43 separate reports (totaling some 10,000 pages) that cover specific improvements to building standards, codes and practices; changes to, or the establishment of, evacuation and emergency response procedures; and research and other appropriate actions needed to help prevent future building failures.Based on nearly 500 comments received during the six-week public review period following the release of the draft WTC towers report on June 23, 2005, the reports—including some of the recommendations—were amended and clarified. The comments on the report also will be made available at

Released November 3, 2005, Updated January 7, 2021