Near Miss: personnel transfer basket hit structure

What happened

During a transfer of two personnel to a platform using the vessel crane, the base bumper of the personnel transfer basket came into contact with the helipad netting rail of the platform. At the time of the incident, an unexpected wave caused the vessel to roll and resulted in the subsequent vertical movement of the vessel crane tip.

The contact was slight and there were no injuries nor damage to equipment reported, however, it was identified that a more serious incident could have occurred in different circumstances.

What went right

• A Permit to Work for the personnel transfer had been approved; this included a passenger toolbox  talk and a risk assessment for the transfer;
• The sea state was considered within limits for personnel transfer basket operations;
• There were rigging personnel positioned at both departure and landing areas for the operation.

What went wrong

• Detailed planning for personnel transfer operations had failed to recognise the potential – notwithstanding the sea state being within limits for such operations – for vessel roll and subsequent vertical movement of the crane and personnel basket;
• Engineering drawings did not provide vertical movement detail for the personnel basket as affected by environmental conditions. 

Root cause

Our member found that the root cause of the incident was insufficient detail in specified working limitations for the vertical movement of the basket when the vessel rolls, and that a minimum safe clearance height above the helideck had not been defined to avoid helideck contact whilst carrying out transfers within the operational limits of the crane.

Lessons/actions

Lift plan to include calculated basket vertical movements corresponding to vessel roll for crane operational limits. As per example drawing.

Members may wish to refer to:

• Provisions Crane damaged by Main Deck Crane
• Equipment on quay damaged when vessel started listing
• Crane contact with pipelay tower resulting in dropped object