Investigation of WTC 1 and 2

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 Full report (298 pages).
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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
• NIST NCSTAR 1-1B: Comparison of Building Code Structural Requirements

• 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 1-2A: Appendixes
  • NIST NCSTAR 1-2B: Analysis of Aircraft Impacts into the World Trade Center Towers, Chapters 1-8
  • NIST NCSTAR 1-2B: Analysis of Aircraft Impacts into the World Trade Center Towers, 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