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Status of Data Collection Efforts

The National Institute of Standards and Technology (NIST) is basing its review, analysis, modeling, and testing work for the World Trade Center (WTC) Investigation on a solid foundation of technical evidence. This requires access to critical data such as building documents, videographic and photographic records, emergency response records, and oral histories, in addition to the samples of steel that have been recovered.

NIST has received considerable cooperation and large volumes of information from a variety of organizations and agencies representing the building designers, owners, leaseholders, suppliers, tenants, first responders, contractors, insurers, news media, survivors, and families of victims. In addition, NIST has received and is grateful for cooperation from The National Commission on Terrorist Attacks Upon the United States (9-11 Commission). The documents and other information relate to the design, construction, operation, inspection, maintenance, repair, alterations, emergency response, and evacuation of the WTC complex.

Local authorities providing information include the Port Authority of New York and New Jersey (PANYNJ or Port Authority) and its consultants and contractors; the New York City Fire Department (FDNY); the New York City Police Department (NYPD); the New York City (NYC) Law Department; the NYC Department of Design and Construction; the NYC Department of Buildings; and the NYC Office of Emergency Management. In addition, the Occupational Safety and Health Administration provided correspondence sent to it regarding the evacuation experience of WTC occupants on September 11, 2001.

NIST also has received information from Silverstein Properties and its consultants and contractors; the group of companies that insured the WTC towers and its technical experts; Nippon Steel; Laclede Steel; U.S. Mineral Products Co. and Isolatek International; Morse Zehntner Associates; W.R. Grace & Co.; Citigroup, formerly Salomon Smith Barney; United Airlines; American Airlines; and Boeing. NIST also received information on floor plans, furnishings, and contents from tenants of all three buildings.

The information from Silverstein and the insurance companies includes the large body of technical work completed by both parties as part of the insurance litigation involving the WTC towers, such as reports on the structural collapse, fire spread and severity, and wind tunnel test results for the WTC towers. In addition, technical experts for both parties independently provided extensive briefings to the WTC investigation team and discussed the tenability environment and the evacuation procedures in the buildings.

NIST has received all of the essential information it needs for the WTC investigation. That information includes NYC 911 tapes, the transcripts of approximately 500 interviews of employees of the FDNY who were involved in WTC emergency response activities, and supporting documents for McKinsey & Company's FDNY study.

Documentary Information Received by NIST

December 2002

  • The original design drawings (structural, architectural, mechanical, electrical, plumbing) and the original fabrication and construction drawings for the WTC towers
  • Tenant alteration application reports, including drawings and specifications, for the WTC towers and WTC 7, and associated construction audit reports
  • Tenant design standards manuals for structural; architectural; heating, ventilating, and air-conditioning (HVAC); fire protection; plumbing; electrical; fire alarm; and construction review
  • Emergency evacuation procedures manuals, including fire safety guide
  • Operations manuals for the fire protection system, including sprinklers, standpipes, alarm system and communication protocols, and water and power supply
  • Operations manuals for the HVAC systems
  • Reports on facility condition surveys and structural integrity inspections for the WTC towers and WTC 7
  • Recent inspection and maintenance reports for the elevators and escalators in the WTC towers; elevator numbering system
  • Reports on pre-design tests of structural components, including dampers for the WTC towers
  • Reports on wind tunnel tests of the WTC towers and wind speed measurements near the WTC site
  • Reports on the 1993 bombing damage assessment and repairs, and documentation of changes made to the evacuation system after 1993
  • Documents related to the location, approval, and inspection of fuel tanks in WTC 7
  • Documents related to fire rating and fireproofing of structural steel members in the WTC towers
  • Documents related to PANYNJ building and fire code requirements and practices
  • Correspondence sent to the Occupational Safety and Health Administration regarding the evacuation experience of WTC occupants on September 11, 2001
  • Documents related to the lease of the WTC towers by Silverstein Properties
  • Reports prepared by McKinsey & Company for FDNY and NYPD
  • Basic FDNY dispatch data, including time of dispatch and unit identification
  • Firefighter fatality and injury data from FDNY

May 2003

  • More than 1,000 hours of recordings made by PANYNJ on September 11, 2001 (from 0705 through 1900 hours) of telephone calls, as well as police, fire, operations, maintenance, security, and other radio transmissions from four distinct locations
  • Personal injury data from FDNY and Port Authority of New York and New Jersey Police Department (PAPD)
  • Handwritten notes on the events of September 11, 2001, by PAPD staff
  • Emergency responder fatality data for FDNY, NYPD, and PAPD
  • WTC list of tenants with contact information from PANYNJ and Silverstein
  • WTC list of occupants issued security badges by PANYNJ
  • Report on WTC smoke management system by Hughes Associates, Inc.
  • Phase I and final reports on fire engineering of WTC steelwork by Buro Happold
  • Transcripts of depositions by two PANYNJ staff in the WTC insurance litigation
  • Documents, videos, and photographs related to the fireproofing of the WTC tower structures
  • WTC floor plan for the fire alarm system and drawings of WTC subgrade plumbing and city water main
  • Information regarding building contents such as partitions and furnishings from a key WTC tower tenant, to characterize the types of combustibles and estimates of the mass loading in the region of the fires
  • FDNY WTC incident summary, September 20, 2001
  • FDNY reports on the fire history of WTC 1, 2, and 7 from 1970 to 2001
  • FDNY reports related to inspections of WTC 1, 2, and 7 from 1999 to 2001
  • FDNY policies and practices on operations specific to the WTC buildings and on accountability of firefighters at incidents
  • FDNY information on dispatched units, apparatus, command posts, and staging areas
  • FDNY information on number of command and company officers and firefighters operating in and around WTC 1, 2, and 7 with number of surviving personnel
  • Detailed briefing on the NYPD communications system, including 9-1-1 system and radio networks

August 2003

  • Design and structural calculations from Leslie E. Robertson Associates (LERA) for the WTC towers, including TV antenna, beams, and beam girders, as well as wind analysis and calculationsCorrespondence from LERA during the time of construction
  • Laclede floor truss shop drawings (1,364 sheets) and other documents on steel and joints
  • Information on steel from Nippon
  • List of WTC drawings in possession of Yamasaki and Associates
  • Information on the flammable contents of the American Airlines B-767 aircraft
  • Information regarding building contents and floor layouts from some WTC tower and WTC 7 tenants
  • Mechanical and electrical specifications for WTC 7
  • Asbestos litigation documents from PANYNJ
  • Underwriters Laboratories, Inc. (UL) test reports regarding spray-on fireproofing from supplier (Isolatek)
  • Correspondence on the selection of W.R. Grace fireproofing products, test data, and UL design listings (W.R. Grace)
  • Data on the WTC internal radio system and FDNY radio repeater from PANYNJ
  • Some FDNY training practices for operations in high-rise buildings
  • Global positioning system coordinates and map where human remains and equipment were located from FDNY
  • Information on FDNY personnel killed on September 11, 2001, and map of fire and Emergency Management Services Command Post Locations
  • NYPD internal communications concerning the terrorist attacks on WTC (43 cassette tapes)
  • Disaster Response Plan, Patrol Guide Procedures, and other guides and manuals from NYPD, including the Unusual Occurrence Report on the 1993 WTC bombing
  • A large portion of NYPD and FDNY extensive photographic and videographic collection
  • Updated badge list of WTC occupants maintained by PANYNJ
  • WTC fire safety and PA/FDNY WTC training videos and pre-September 11, 2001 WTC photographs

September 2003

  • Information on the flammable contents of the United Airlines B-767 aircraft
  • Documents from PANYNJ on accessibility for disabled persons, active fire protection systems, and adoption of revisions to NYC Building Code
  • Elevator and escalator contract information from PANYNJ
  • Status of changes to WTC towers (March 1973) from PANYNJ
  • Transcripts from September 11 PAPD audiotapes, police reports, and PAPD special awards ceremony documents for September 11, 2001
  • Additional documents from PANYNJ on asbestos litigation

October 2003

  • Supporting documents for McKinsey & Company's FDNY and NYPD studies
  • Review of UL test reports regarding spray-on fireproofing from supplier (W.R. Grace)
  • Information from Boeing on flammable contents of aircraft that contributed to fires

May 2004

  • Review of NYC 9-1-1 tapes and logs, transcripts of about 500 first responder interviews with employees of the FDNY who were involved in WTC emergency response activities
  • General description of WTC building systems and capital program
  • WTC documents presented as exhibits in asbestos litigation
  • Additional documents on WTC maintenance services, accessibility, elevators, code compliance, fire rating, fire detection system, fire alarm system, etc
  • Photographs of WTC 7 construction project
  • Architectural and HVAC drawings for WTC 7, including modifications
  • Well in excess of 6,000 photographs representing more than 185 professional and amateur photographers. Organizations that have provided materials include FDNY, NYPD, Associated Press, Corbis, Reuters, The New York Times, The New York Daily News, and the Star Ledger. Many organizations have provided both published and unpublished photographs.
  • In excess of 150 hours of videotapes from news media (NBC, CBS, ABC, CNN, and local New York stations WABC, WCBS, WNBC, WPIX, WNYW, and New York One), FDNY, NYPD, and more than 20 individuals. In many cases, the videos provide not only broadcast material (known as air checks), but also material that was recorded but not broadcast (known as outtakes).

Pending Requests for Documentary Information

The few NIST requests for materials that are lost, currently pending, or not yet located include:

  • Original contract specifications for WTC towers (lost in the collapse of the buildings)
  • Construction and maintenance logs for WTC 1, 2, and 7 (lost in the collapse of the buildings)
  • Calculations and analyses that supported the original aircraft impact studies (lost in the collapse of the buildings)
  • Descriptions of partitions and furnishings in most of the tenant spaces of WTC 2 and WTC 7 in the fire and impact zones
  • Shop drawings showing connection details of WTC 7

NIST is making efforts to assemble this information from various sources because much of it was lost when the buildings collapsed. NIST continues to pursue other materials that can further clarify some aspects of the Investigation.

Released July 21, 2004, Updated January 13, 2023