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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 1-2B: 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)