WTC investigators seek more photos
WASHINGTON (CNN) --Engineers investigating the structural failures that led to the collapse of the World Trade Center buildings asked Monday for more photographs of the aftermath of the September 11, 2001, terrorist attack.
"We are especially interested in WTC Seven and views from the south and west faces of the WTC Towers," said Shyam Sunder, the lead investigator for the National Institute of Standards and Technology, or NIST, which is part of the Commerce Department.
Building Seven, a 47-story structure, was damaged when Buildings One and Two, the Twin Towers, collapsed across the street. Building Seven collapsed a few hours later.
Sunder said the images could prove critical to determining how the fire spread and what caused the structures to collapse.
"There continues to be a dearth of photos of the south side of WTC Seven. It has been suggested that the debris from the collapse of WTC One struck WTC Seven on this side and ignited the fires that led to its ultimate collapse."
The World Trade Center towers collapsed after a pair of hijacked airliners slammed into the buildings.
Investigators know fuel from the planes burned around critical support structures that were also damaged by the impacts, but the exact cause of the failures and sequences of events have not been determined.
Sunder said investigating engineers need the photographic evidence to help them improve building and fire codes, not for litigation purposes.
He urged persons or organizations with such pictures to contact NIST at [email protected], by fax at 301 975-6122 or through the U.S. mail at WTC Technical Information Repository, NIST, 100 Bureau Drive, Stop 8610, Gaithersburg, Maryland, 20899-8610.
"We're not looking for spectacular photographs," Sunder said. "Those photographs have appeared in the press."
He said he believed there was a lot of unpublished information that would help investigators determine how the fires spread in different parts of the towers and what sort of ventilation was available to fuel the fires.
"We aim to learn enough so that we can point to recommended improvements in the way in which we design, construct, maintain and use our buildings, especially high rises," said NIST Director Arden Bement.
The NIST investigation began in August and is expected to be complete in about 20 months.
