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H₂S leak umbilical laying

A member has reported an incident in which there was a H₂S (Hydrogen Sulphide) leak during umbilical laying operations. A deck-hand and others on deck noticed a smell of rotten eggs. Vessel management were informed, activities were halted and the area isolated. A specialist contractor was brought in to test the air for H₂S, and when the area was tested clear, operations were resumed. No-one was contaminated and no-one reported feeling sick or ill.

The following was noted:

  • Owing to lack of awareness that there might be H₂S in the umbilical, there were no control measures in place;
  • Appropriate tests and measurement of potential H₂S should be made before and during such umbilical deployment operations;
  • If leaks are found, umbilical operations should be halted until a specialist contractor can be brought in to assist in dealing with the gas.

Safety Event

Published: 25 January 2012
Download: IMCA SF 01/12

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