MAIB safety warning on chain link failure following loss of life on scallop dredger

The failure of a chain link in the lifting arrangement for the dredging gear on the scallop dredger Honeybourne III led to the gear falling without warning. The gear struck a deckhand working on the deck below; the deckhand suffered serious head injuries and died on board.

The configuration of a chain led over a static pin as part of the quick-release gear for the lifting arrangement is commonly used on board scallop dredgers and beam trawlers. However, instances of their failure have been the subject of previous investigations.

The MAIB has issued safety lessons:

Safety lessons

• The recent recorded accidents and failures of chain links leading over a static pin as part of a quick-release mechanism indicate the significant risk of such arrangements failing when loads are applied to the chains. These arrangements can induce complex loading forces in the chain links, leading to excessive wear on the chain links and significantly reducing the chain strength.
• The location of the chain links at the derrick head and the fact that the deterioration of the chain links may not be easily visible mean that it can be difficult to inspect and identify degradation of the quick-release arrangement.
• The potential failure of chains used in this manner presents an unacceptable level of risk to crew members working on the deck below.

The MAIB recommend that all owners, operators and skippers of scallop dredgers and beam trawlers that use chain as part of the derrick head quick-release mechanism urgently ensure that a suitable and sufficient assessment of the risk of a failure of the derrick quick-release mechanism chain has been undertaken and documented.

Read the bulletin at Safety warning issued following a chain failure on scallop dredger Honeybourne III with loss of 1 life – GOV.UK (www.gov.uk)