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Workboat Failed During Transfer Operations Due to Fuel Contamination

What happened?

The Marine Safety Forum (MSF) has published a Safety Alert regarding an incident in which a workboat’s engine cut out. The incident occurred during a crew transfer operation by workboat. The crew’s engineer made several unsuccessful attempts to restart the engine. The Coxswain made contact with the vessel Master and advised him of the situation. The vessel proceeded to attend and the workboat was safely recovered.

Sediment build-up at the bottom of the workboat tank

What went wrong? What were the causes?

Vessel engineers discovered that the fuel in the tank was contaminated due to water condensation causing a build-up of bacteria. The source of contamination was water or moisture in the tank due to condensation in the tank head space; this resulted in a build-up of bacteria turning into sediment. The sediment caused the fuel oil fine filter to clog preventing the engine from starting.

Planned maintenance system (PMS) instructions with respect to inspection and maintenance were clear, but had not been followed. The vessel did not hold spare filters on board.

What actions were taken? What lessons were learned?

  • Check fuel and tank quality through planned maintenance inspections, treat and/or clean as applicable;
  • Ensure workboat fuel tank levels are maintained to prevent condensation/water building up;
  • Ensure a stock of essential fuel filters are held on board.

Members may wish to refer to the following incident:

Safety Event

Published: 19 March 2018
Download: IMCA SF 06/18

Relevant life-saving rules:
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