The U.S. Coast Guard has issued a Safety Alert urging operators of liquified gas carriers to takes steps to reduce risk in the handling of cargo and hydrates.
The alert resulted from a fire in the cargo compressor room of a liquified petroleum gas (LPG) carrier in which unsafe cargo handling is a suspected factor. The incident occurred while an unsafe approach was taken in the manual draining of hydrates from a line on the outlet of re-liquifaction condensers. Flow became constricted in piping near an expansion valve due to hydrates freezing, creating a fire hazard because pressure increased and there were possible leaks. Investigators theorize that a spark from fallen flange blank may have ignited the area. The fire destroyed electrical cables and gaskets.
The Coast Guard strongly recommends that operators specify a safe procedure for removing hydrates, following industry best practices. Crews who transport dangerous cargoes need “routine and frequent” training, which should address risks in releasing LPG in enclosed spaces. The training should include the proper use of gas detection alarms, ventilation, leak identification, managing hydrates and reducing static electricity.
Below is the full text of the Coast Guard’s Safety Alert, with photos of the compressor room components: