What happened on 11 September, 2001?

On 11 September 2001, terrorists attacked the United States by hijacking four commercial airliners and crashing them into their targets.

Two were deliberately crashed into the north and south towers of the World Trade Centre in New York. One was crashed into the Pentagon, while the other was believed to be headed for the United States Capitol or the White House, but it was instead crashed into a field in Pennsylvania after the passengers onboard, who had learned of the previous attacks, revolted against the hijackers.

With nearly 3,000 tragically killed, it remains the deadliest terror attack in history.

How did the fire at the World Trade Center spread?

Following the collisions a huge jet fuel-fed blaze engulfed multiple floors of both the north and south towers. Both towers collapsed within two hours, destroying other structures in the surrounding area.

What did the industry learn from the fires as a result of the September 11 attacks?

The attacks led to reviews and revisions of building codes and high-rise fire protection standards worldwide, including sprinkler systems, stairwell integrity and structural redundancy.