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# Draft Reports from the NIST World Trade Center Disaster Investigation

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**DRAFT**
In April 2005, NIST released **for public comments** the **DRAFT**reports documenting the Federal Building and Fire Safety Investigation of the World Trade Center Disaster. These reports included the draft summary report on the Investigation of the WTC Towers, project reports, and supporting technical topic reports. These reports were issued in draft form with a six-week period for public comment. Public comments were accepted during the period commencing June 23rd and ending at 5 p.m. EDT on August 4th. 2005. 
                  -  Public comments received by NIST, June 23 - August 4, 2005  (PDF, 82.3 MB) 

## DRAFT Reports released for public comment in April 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 Towers

(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)  Design and Construction of Structural Systems (Appendices A-B)
                    - (NIST NCSTAR 1-1A)  Design and Construction of Structural Systems (Appendices 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)  Maintenance and Modifications to Structural Systems (Appendices A-G)
                  - (NIST NCSTAR 1-1D)  Fire Protection and Life Safety Provisions Applied to the Design and Construction of WTC 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)  Documentation of the Fuel System 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)  Analysis of Aircraft Impacts into the World Trade Center Towers (Chapters 9-11)
                    - (NIST NCSTAR 1-2B)  Analysis of Aircraft Impacts into the World Trade Center Towers (Appendix A)

(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)  Damage and Failure Modes of Structural Steel Components (Appendices A-G)
                  - (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)  Visual Evidence, Damage Estimates, and Timeline Analysis (Chapter 9-Appendices A-M)
                  - (NIST NCSTAR 1-5B)  Experiments and Modeling of Unprotected Structural Steel Elements Exposed to a 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 1-5G)  Fire Structure Interface and Thermal Response of the World Trade Center Towers
                  - (NIST NCSTAR 1-5F)  Computer Simulation of the Fires in 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

(NISTNCSTAR 1-8) The Emergency Response Operations
                  - NISTNCSTAR 1-8  The Emergency Response Operations (Appendices A-L)

----

On August 21, 2008, NIST released **for public comments DRAFT REPORTS** documenting the Federal Building and Fire Safety Investigation of the World Trade Center Disaster – **WTC 7**. These reports include the draft summary report on the Investigation of WTC Building 7, 1 project report, and supporting technical topic report. The Comment Period Closed on September September 15, 2008.  Comments were especially encouraged on the draft summary report, which contains the principal findings and recommendations for changes to codes, standards, and practices. Comments were accepted via Web site, e-mail, fax, and regular mail. 
                  - Public comments received by NIST August 21 - September 15, 2008  (PDF, 32.6 MB)

## DRAFT Reports released for public comment in August 2008:

> 
(NIST NCSTAR 1A) Report on the Collapse of World Trade Center Building 7

(NIST NCSTAR 1-9, Volume 1) Structural Fire Response and Probable Collapse Sequence of World Trade Center Building 7, **Volume 1**

(NIST NCSTAR 1-9, Volume 2) Structural Fire Response and Probable Collapse Sequence of World Trade Center Building 7, **Volume 2**
- (NIST NCSTAR 1-9A)  Global Structural Analysis of the Response of World Trade Center Building 7 to Fires and Debris Impact Damage 

Disaster and failure studiesFireDisaster and failure studiesDisaster and failure studiesStructural engineering

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