The National Institutes of Standards and Technology (NIST) conducted large amounts of research regarding various aspects of 9-11 and has issued many hundreds of pages of reports. Their index to this work is here.
At least one of these reports has received widespread criticism for its apparent deep flaws.
Note: As of 2011-08-07, wtc.nist.gov appears to be down. This is where the overwhelming majority of NIST's 9/11 documents are stored. archive.org does not seem to have any copies of pages or documents on that site either. This report in particular apparently has some evidence about temperatures which should be included here. This server is still linked to from here as being the official source for "World Trade Center disaster investigation".
 Quotes About
- Fire Engineering magazine editor calls the NIST investigation "half-baked farce"... "a full-force, full-throttle investigation is necessary"[?]
- did not mention WTC7 at all (not entirely true -- later investigations did cover this)
- only addresses sequence of events up to the initiation of collapse, does not attempt to explain the collapse itself (how is this useful?)
- the collapse itself is waved away as "inevitable", regardless of any historical precedent
- UL investigator Kevin Ryan pointed out that tests NIST hired UL to do heated (something) to 2000° for up to 2 hours and only resulted in sag of 4 inches, but NIST used a sag of 42 inches in their simulation
- NIST refuses to allow access to their simulations or data, despite the triviality of the expense and the fact that the information should all be in the public domain since it was produced by government employees on the job and is not classified (there is a law about this somewhere...) This was supposed to be a public investigation, and yet the details have been kept secret.
- The report does not address any of the evidence of controlled demolition, even to dismiss it.
- 2005-12-08 (v1.0) Building a Better Mirage "NIST's 3-Year $20,000,000 Cover-Up of the Crime of the Century" by Jim Hoffman
 version 2
- 2008-06-25 [Talk|Index] Leaked NIST Docs: "Unusual" Event Before Collapse Of WTC 7 § Leaked NIST documents reveal that an "unusual" "jet of flames" shot out of several windows of WTC7 after most of the fire had already died down.
- 2007-11 [Talk|Index] The Role of Metallurgy in the NIST Investigation of the World Trade Center Towers Collapse § “This article describes the major findings of the metallurgical part of the NIST WTC investigation and shows how the findings were integrated into the investigation.”