Skip to main content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Disaster and Failure Studies Repository

World Trade Center Disaster Investigation Materials

Overview:

On August 21, 2002, the National Institute of Standards and Technology (NIST) announced its building and fire safety investigation of the World Trade Center (WTC) disaster. 

The goals of the investigation of the WTC disaster were:

  • To investigate the building construction, the materials used, and the technical conditions that contributed to the outcome of the WTC disaster after terrorists flew large jet-fuel laden commercial airliners into the WTC towers.
  • To serve as the basis for:
    • Improvements in the way buildings are designed, constructed, maintained, and used;
    • Improved tools and guidance for industry and safety officials;
    • Recommended revisions to current codes, standards, and practices; and
    • Improved public safety

For more information, see World Trade Center Disaster Investigation web pages.

NOTICE 

The NIST World Trade Center Disaster Investigation materials are stored in the NIST Google GSuite account that is owned by NIST.  The repository contains a compilation of images, videos and documents collected during and after disaster and failure events studied by the National Institute of Standards and Technology (NIST), as well as data generated from research on those events. The materials in the repository serve as an historical archive. Some of these materials may contain offensive language or images/videos that some may find graphic. NIST is providing these materials as a public service and to comply with regulations that require federal agencies to provide equal access to data available for public release.

Materials available in the repository may be protected by copyrights owned by private individuals or organizations, and may be subject to restrictions on use. Where known by NIST, the copyright owner is identified with the image. You may want to obtain legal advice prior to further dissemination.

See the NIST Privacy Policy page for general policy information on all NIST web pages.


COLLECTED MATERIALS

The collected materials available on this site were accumulated with the assistance of the media, public agencies and individual photographers.  Materials are available in the following categories:

Organized Photos and Video Clips 
Original Video from Tapes
    Other Photos and Videos

NIST-GENERATED PHOTOS, VIDEOS, AND COMPUTER SIMULATIONS

This section contains photos, videos, and computer simulations created during NIST’s investigation of the World Trade Center Disaster that support the findings of the Investigation.  These supporting materials are available in the following categories:

Images of Collected Steel
Computer Simulations
Fire Tests and Analysis

Below are the final reports for the Investigation into the collapses of the World Trade Center Towers (WTC 1 and WTC 2) and into the collapse of World Trade Center Building 7 (WTC 7.)

Final Reports from the NIST Investigation of the World Trade Center Disaster

Final Reports released in September 2005:

 

Final Reports released in November 2008:

NIST NCSTAR 1A:  Final Report on the Collapse of World Trade Center Building 7 *

* List of January 2009 Text Changes to the NIST Reports of the Federal Building and Fire Investigation of the World Trade Center Disaster, NCSTAR 1A, NIST NCSTAR 1-9, and NIST NCSTAR 1-9A


About Tags, Attributes and Metadata

A subset of the materials gathered for the World Trade Center Investigation, including photographs and video clips, was organized into a searchable database in which the images and video clips were characterized using tags and attributes.   This collection of materials is available under the heading "Organized Photos and Video Clips."

TAGS:  A set of keywords, or "tags", was established to be used for binary tags (i.e. 1 or 0, yes or no.)  

ATTRIBUTES:  Attributes were also used to record other information such as "View Direction" or "Photographer."

The process of analyzing and assigning attributes and tags to these images and video clips did not include assigning every possible appropriate attribute or tag to every image and video clip in the database. Therefore, it is possible that some images and video clips in this collection may not be assigned an attribute or tag that is in fact appropriate for that image or video clip. 

Tags and attributes were only assigned to the photos and video clips included under the heading "Organized Photos and Video Clips," although copies of these same photos or video clips might also be found under other headings such as "Other Photos and Video" and "Original Video from Tapes," and in those cases, will not have been assigned tags or attributes. Searching using the "Tag Cloud" or the Advanced Search "Search Tags" and "Search Attributes" options will only return results from the materials in the "Organized Photos and Video Clips" collection. Searching using the Advanced Search "Search Titles" option will return results from the entire repository.

EMBEDDED METADATA:  Some of the photos and videos contain information that was embedded by the camera or the photographer. NIST takes no position as to the accuracy of any such information. 


Copyright and Usage

This repository contains a compilation of images, videos and documents collected during and after disaster and failure events studied by the National Institute of Standards and Technology (NIST), as well as data generated from research on those events.

Materials available in the repository may be protected by copyrights owned by private individuals or organizations, and may be subject to restrictions on use.

Where known, NIST has identified the copyright owner with the image, video or document. Materials not identified with copyright information may be protected by copyrights not known by NIST. You may want to obtain legal advice prior to further dissemination. NIST does not maintain current contact information for copyright holders.

Some of these materials may contain offensive language or images/videos that some may find graphic.

NIST is providing these materials as a public service and to comply with regulations that require federal agencies to provide equal access to data available for public release.


Accessibility

The National Institute of Standards and Technology (NIST) is committed to making every document on its website accessible to the widest possible audience, including persons with visual disabilities. The collection of photos and videos presented here contains thousands of images and hundreds of hours of video footage. An effort to fully provide audio transcripts and visual descriptions of these materials would pose an undue burden on NIST at this time. If you have any questions regarding the accessibility of the materials provided on these web pages, please contact inquiries@nist.gov.

Privacy

See the NIST Privacy Policy page for general information for this and all NIST web pages.

 

Contacts

Created November 26, 2019, Updated August 6, 2020