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# Final Reports from the NIST World Trade Center Disaster Investigation

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## 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 1-2B:  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  *

** Errata for NIST NCSTAR 1A, NIST NCSTAR 1-9, and NIST NCSTAR 1-9A, Federal Building and Fire Safety Investigation of the World Trade Center Disaster: Structural Fire Response and Probable Collapse Sequence of World Trade Center Building 7 (January 2009, April 2012, and June 2012)*

Disaster and failure studiesResilienceResilienceFireDisaster and failure studiesDisaster and failure studiesStructural engineering

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