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Near-miss: Incorrect rigging of life raft hydrostatic release

IMCA’s attention has been drawn to a near miss in which it was found that the hydrostatic release on a life raft was not correctly rigged. This was discovered following the replacement of a life raft. It was noticed that if the collar on the Senhouse slip was lifted for life raft launch, it would not release the strap as the lashing that connected it to the hydrostatic release unit was tied too tightly, so the arm would not easily slip through and release. This was due to the hitches in the lashing being carried on too far up towards the slip, not leaving enough room for the arm of the slip to move sufficiently.

Lashing tied too tight where usually connected to Senhouse slip

The following points are to be noted:

  • The Senhouse slip should not be attached through a lashing and should be directly attached to the hydrostatic release unit;
  • Hydrostatic release units are fitted with a yellow plastic that aids the release of the Senhouse slip when released. If fitted through a lashing, this can create friction making the operator unable to launch the life raft safely;
  • The lashing can still be used in the securing of the life raft, but in a different position. Care should be taken to ensure that the painter line is tied through the red ring on the Hydrostatic release unit.

Further information on correct securing of life rafts can be found in the UK Marine & Coastguard Agency (MCA) Marine Guidance Note 343.

Correctly stowed HRU on life raft
Incorrectly rigged HRU

Safety Event

Published: 12 May 2017
Download: IMCA SF 10/17

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