CSB: Process used at Kleen Energy plant 'unsafe'

March 4, 2010

A type of cleaning process used in the natural gas power industry is "inherently unsafe" and likely caused last month's deadly blast at the Kleen Energy plant in Middleton, CT, the Chemical Safety Board recently warned.

During the process, known as a "gas blow," natural gas is forced at high pressure through pipes to remove debris before venting into the atmosphere. It is a common practice in the industry during the commissioning of new or modified gas pipes at industry facilities, according to CSB member Don Holmstrom, lead investigator of the Kleen Energy plant explosion.

A gas blow was being performed at the Kleen Energy plant prior to the Feb. 7 explosion, which killed five workers. The gas was released into a congested area that likely slowed its dispersion, allowing it to build up above an explosive limit and eventually ignite by some unknown source, Holmstrom said in a Feb. 25 statement (.pdf file) recommending against the use of gas blows. CSB said it is investigating what codes or regulations cover the process, and so far has not found any.