The facility, which is called a "gas governor" and consists of a large slab of concrete, a flue pipe and a control box, is intended to regulate gas supply in the area.

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New techniques have been developed to "sidetrack" a well when the pipe gets stuck or to control the pressures and temperatures found five miles down into the earth's crust with blow-out preventers and special purpose high-tech drilling rigs.

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The friction caused by the gas bubble pushing up the pipe and displacing the drilling mud used to control the pressure could have created a static charge that ignited the gas into a fireball.

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At 8:20 p.m. on the day of the explosion the pressure data suggest there was a constant flow of sea water being pumped into the drill pipe that was displacing the heavier mud system which was the primary pressure control for the well.

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With full control of its plant in Abu Dhabi, Hilong has an additional drill pipe production capacity of 11, 023 tons, compared with its 44, 753 tons on the mainland.

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