Video report by Jonathan Brown
Paul Berriff was making a documentary in New York City in 2001, he witnessed the hijacked aircraft crashing into the World Trade Center and filmed firefighters trying to rescue people from the buildings.
He was knocked unconscious by falling debris as the towers collapsed, but his camera kept rolling with footage being used in a documentary the next year.
He told ITV News: "I like to live every day and enjoy everything because you just never know.
"Every minute, bang, goes just like that. I mean that day, we wouldn't have been where we were, the firefighters wouldn't have set up their command post and parked all their fire trucks underneath the buildings had they known they were going to come down."
Paul was stood with firefighters just meters away from the World Trade Center when the South Tower collapsed
Describing the moment he said: "It was just peeling away like a big umbrella and then all this debris started coming towards us.
"It was a roar that I can't really explain, it was as though you were on the runway at Heathrow with dozens of jumbo jets coming up behind you - it was just an amazing, amazing sound.
"So we were running down the street and then the next thing I remember is the camera leaving my hand in slow motion and then everything goes black."
Paul believes he was unconscious for about half an hour and said that the scene was "apocalyptic" when he woke up amid smoke and debris.
He added: "We worked out that I was probably the first live person right in the epicentre and all hell blazing around me."
He then spent a year documenting the effects that the terrorist attack had on the firefighters who risked their lives that day and on the clear-up of ground zero.
Paul has kept his camera, which still bears the scars and dust from that day in his home as a reminder of how precious life can be and how important it is to talk.
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