The Piper Alpha oil platform suffered a catastrophic explosion, leaving most workers trapped in an inferno at sea. This disaster led to major changes in offshore safety - but what really caused it?

In April 2010, there is no oil exploration operation in the Gulf of Mexico to compare with the Deepwater Horizon oil rig with its size ... the worst environmental disaster in US history.

(CNN)-- Here are the latest developments on the oil disaster in the Gulf of Mexico, which unfolded after the oil rig Deepwater Horizon exploded on April 20: President Barack Obama delivers strong ...