A petrochemical plant has been fined after ethylene, a flammable gas was released from a cracked pipe at the Ethylene Plant. On May 2, 2017, approximately 17 tons of ethylene were released from the pipe. This leak precipitated the formation of a flammable gas cloud of around 2,295,453 cubic ft. The gas cloud was seen to move through a congested area of the plant reaching ground level. An investigation by the Health and Safety Executive (HSE) identified that the immediate cause of an unplanned shutdown on the compressor was due to a ‘non-routine maintenance activity related to the changeover of a redundant electronic control card in the compressor anti-surge system.