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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:
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:
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:
- NIST NCSTAR 1: Federal Building and Fire Safety Investigation of the World Trade Center Disaster: Final Report of the National Construction Safety Team on the Collapses of the World Trade Center Tower
- NIST NCSTAR 1-1: Design, Construction, and Maintenance of Structural and Life Safety Systems
- NIST NCSTAR 1-1A: Design and Construction of Structural Systems
- NIST NCSTAR 1-1A appendixes A-B
- NIST NCSTAR 1-1A appendixes C-G
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NIST NCSTAR 1-1B: Comparison of Building Code Structural Requirements
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NIST NCSTAR 1-1C: Maintenance and Modifications to Structural Systems
- NIST NCSTAR 1-1C appendixes
- NIST NCSTAR 1-1D: Fire Protection and Life Safety Provisions Applied to the Design and Construction of World Trade Center 1, 2, and 7 and Post-Construction Provisions Applied after Occupancy
- NIST NCSTAR 1-1E: Comparison of Codes, Standards, and Practices in Use at the Time of the Design and Construction of World Trade Center 1, 2, and 7
- NIST NCSTAR 1-1F: Comparison of the 1968 and Current (2003) New York City Building Code Provisions
- NIST NCSTAR 1-1G: Amendments to the Fire Protection and Life Safety Provisions of the New York City Building Code by Local Laws Adopted while World Trade Center 1, 2, and 7 Were in Use
- NIST NCSTAR 1-1H: Post-Construction Modification to Fire Protection and Life Safety Systems of the World Trade Center Towers
- NIST NCSTAR 1-1I: Post-Construction Modifications to Fire Protection, Life Safety, and Structural Systems of World Trade Center 7
- NIST NCSTAR 1-1J: Design, Installation, and Operation of Fuel Systems for Emergency Power in World Trade Center 7
- NIST NCSTAR 1-2: Baseline Structural Performance and Aircraft Impact Damage Analysis of the World Trade Center Towers
- NIST NCSTAR 1-2A: Reference Structural Models and Baseline Performance Analysis of the World Trade Center Towers
- NIST NCSTAR 1-2B: Analysis of Aircraft Impacts into the World Trade Center Towers (Chapters 1-8)
- NIST NCSTAR 1-2B: Chapters 9-11
- NIST NCSTAR 1-2B: appendixes
- NIST NCSTAR 1-3: Mechanical and Metallurgical Analysis of Structural Steel
- NIST NCSTAR 1-3A: Contemporaneous Structural Steel Specifications
- NIST NCSTAR 1-3B: Steel Inventory and Identification
- NIST NCSTAR 1-3C: Damage and Failure Modes of Structural Steel Components
- NIST NCSTAR 1-3C: appendixes
- NIST NCSTAR 1-3D: Mechanical Properties of Structural Steels
- NIST NCSTAR 1-3E: Physical Properties of Structural Steels
- NIST NCSTAR 1-4: Active Fire Protection Systems
- NIST NCSTAR 1-4A: Post-Construction Fires prior to September 11, 2001
- NIST NCSTAR 1-4B: Fire Suppression Systems
- NIST NCSTAR 1-4C: Fire Alarm Systems
- NIST NCSTAR 1-4D: Smoke Management Systems
- NIST NCSTAR 1-5: Reconstruction of the Fires in the World Trade Center Towers
- NIST NCSTAR 1-5A: Visual Evidence, Damage Estimates, and Timeline Analysis (Chapters 1-8)
- NIST NCSTAR 1-5A: Chapters 9-appendix C
- NIST NCSTAR 1-5A: appendixes D-G
- NIST NCSTAR 1-5A: appendixes H-M
- NIST NCSTAR 1-5B: Experiments and Modeling of Structural Steel Elements Exposed to Fire
- NIST NCSTAR 1-5C: Fire Tests of Single Office Workstations
- NIST NCSTAR 1-5D: Reaction of Ceiling Tile Systems to Shocks
- NIST NCSTAR 1-5E: Experiments and Modeling of Multiple Workstations Burning in a Compartment
- NIST NCSTAR 1-5F: Computer Simulation of the Fires in the World Trade Center Towers
- NIST NCSTAR 1-5G: Fire Structure Interface and Thermal Response of the World Trade Center Towers
- NIST NCSTAR 1-6: Structural Fire Response and Probable Collapse Sequence of the World Trade Center Towers
- NIST NCSTAR 1-6A: Passive Fire Protection
- NIST NCSTAR 1-6B: Fire Resistance Tests of the Floor Truss Systems
- NIST NCSTAR 1-6C: Component, Connection, and Subsystem Structural Analysis
- NIST NCSTAR 1-6D: Global Structural Analysis of the Response of the World Trade Center Towers to Impact Damage and Fire
- NIST NCSTAR 1-7: Occupant Behavior, Egress, and Emergency Communication
- NIST NCSTAR 1-7A: Analysis of Published Accounts of the World Trade Center Evacuation
- NIST NCSTAR 1-7B: Technical Documentation for Survey Administration: Questionnaires, Interviews, and Focus Groups
- NIST NCSTAR 1-8: The Emergency Response Operations
- NIST NCSTAR 1-8: Appendixes A-L
Final Reports released in November 2008:
NIST NCSTAR 1A: Final Report on the Collapse of World Trade Center Building 7 *
- NIST NCSTAR 1-9: Structural Fire Response and Probable Collapse Sequence of World Trade Center Building 7, Volume 1 and 2 *
- NIST NCSTAR 1-9A: Global Structural Analysis of the Response of World Trade Center Building 7 to Fires and Debris Impact Damage *
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 [at] nist.gov (inquiries[at]nist[dot]gov).
Privacy
See the NIST Privacy Policy page for general information for this and all NIST web pages.
Contacts
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WTC Contact