December 9, 2010 - The explosion which caused the Gulf of Mexico oil spill took place shortly after a man who was monitoring vital safety equipment decided to leave his workstation for a cigarette break. Joseph E Keith, an employee of the Halliburton subsidiary Sperry Sun, told investigators that he failed to realise that the well was filling with dangerous levels of crude oil and natural gas because he was in the canteen, having a smoke and a cup of coffee.
By the time Mr Keith had resumed watching his monitors, which were tracking pressure levels on the Deepwater Horizon rig, the safety gauges had returned to normal, according to testimony he gave to the joint Coast Guard-Interior Department panel in Houston.
Not long afterwards, a huge explosion on the BP rig killed 11 people, injured 17 others, and caused oil to begin leaking into the Gulf. Over the ensuing three months, some 206 million gallons were released, in what is believed to be the worst accidental spill in history.
Reference: Smoking kills: Spill blamed on cigarette break Deepwater Horizon safety official admits he missed warning signs before explosion By Guy Adams in Los Angeles, Independent.co.uk, 12/9/2010.