"Many New Yorkers literally pulled it from their fire escapes and from the window jambs of their apartments and have kept it over all these years…We've been able to trace back and realize -- this is a business card, this was a document, this was a desk memo pad that came from the desk of someone unfortunately who perished that day," said Ramirez.
The extensive collection of newly released photos includes work by both amateur and professional photographers who submitted their images to the National Institute of Standards and Technology (NIST) during their investigation of the World Trade Center towers' structural failures. The photos were released following a Freedom of Information Act request filed by ABC News last year.
Ramirez says that while the collection retains tremendous emotionality for people who view it, the photos offer a meaningful reminder of just how far we've come.
"Although 9/11 was an event that certainly set in motion a cascade of political consequences and economic consequences, it is ultimately a great revealer of the human spirit. It was a moment when the essence of who you were -- what you were able to do under extraordinary circumstances, how you could help, how you could comfort -- was revealed."
ABC News' Jason Ryan, Pierre Thomas, Jack Cloherty, Lisa Jones and The Associated Press contributed to this report.