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Crew member in small boat slipped and dislocated shoulder

What happened

A person was kneeling down in a workboat and was injured when the boat moved suddenly as a result of the sea state. The boat (a small workboat used in diving operations) pitched forward and hit a Catenary Anchor Leg Mooring Buoy. The injured person automatically braced himself by placing a hand on the internal structure of the boat, however the impact on his arm resulted in him getting a dislocated shoulder.

What went right

  • Weather conditions were determined as favourable for operations and dive punt operations were being undertaken in accordance with company requirements;
  • The injured person had re-positioned himself into the lower section of the vessel to minimise the risk of falling overboard whilst going about his work;
  • After the incident, emergency response procedures were implemented, and the injured crew person was subsequently transferred to the main vessel for medical treatment.

What went wrong

The crew member, whilst he had earlier used some situational awareness to safely re-position himself, had not foreseen the new risks of sudden movement of the boat associated with where he was now working. Work was now being carried out in a location not covered in the risk assessment. He thought he would be safer, but he wasn’t.

What was the cause

  • Immediate cause was an unexpected movement of the working environment causing human instinctual behaviour leading to injury;
  • Our member found the root causes to be:
    • Risk assessments did not include operational activities being performed in the boat;
    • The requirement for additional equipment being supplied to operational areas and how this was to be undertaken was not adequately addressed within project planning procedures.


  • Plan and consider human instinctual behaviour within risk assessments.
    • An example would be when you call someone’s name when they’re in a space with low headroom, and they automatically look up – and bang their head;
  • Look closely at the adequacy of toolbox talks and prestart meetings for small boat work.

Members may wish to refer to

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