Exposure to residual hydrocarbons when breaking containment

Hydrocarbon pipework had been isolated and flushed. The 3” section, connected to the 1” bypass section via a take-off, was changed out successfully.

As the final cut was made to the horizontal section of the 1” bypass, a release of a small amount of trapped residue/vapour occurred.

The following morning, personnel presented to the medic due to exposure to hydrocarbon vapours.

Investigation findings:

Examination of the removed 1” bypass revealed a solid partial blockage which may have contributed to the trapping and release of residue/vapour.

As the preparatory pipework flush appeared to have been successful, the possibility of a blockage and trapped residue/vapour had not been recognised nor mitigated against.

Despite exposure to released vapours, the work party personnel continued working for a few moments to complete the task.