The Nautical Institute’s latest Mars Report describes how a crew member on board a general cargo vessel died of fumigation poisoning. Among other things, the Institute warns that masters and crew of vessels carrying fumigated cargoes must be aware of the potential impacts of changing ventilation arrangements.

The Nautical Institute gathers reports of maritime accidents and near-misses. It then publishes these so-called Mars Reports (anonymously) to prevent other accidents from happening. A summary of this incident:

A small general cargo vessel with seven crew berthed to load a cargo of corn in bulk. Loading commenced after preparation and cleaning of the hold. The gas tight integrity of the hold was not tested before loading, even though it was intended to undertake in-transit fumigation after loading.

Fumigation specialists arrived at the vessel once loading was complete. They verbally confirmed with the master that the hold was suitable for fumigation. Several bags of aluminium phosphide fumigant were then placed in the hold. The plan was to provide a dose of 1 g of active ingredient per cubic metre of cargo.

The hatches were closed, and the master was given a briefing document pack and gas detection equipment for testing for the presence of the fumigant inside the accommodation and engine room. The chief officer was given training on the use of the gas detection equipment. According to these instructions, tests were to be conducted every eight hours.

The vessel departed the next morning with the favourable tide. At 0800, the chief officer carried out an initial check for the presence of the fumigant. He tested two locations in the accommodation and one in the engine room. These checks were repeated at 2000 that evening and at 0800 the following day.

During this period, the weather deteriorated and the master adjusted the passage plan to reduce the motion of the vessel. At approximately 1030 on the second day out of port, a significant wave caused flooding in the galley and store through the ventilation trunking. The accommodation ventilation flaps were shut and the ventilation system stopped.

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After lunch, the crew who were not working retired to their cabins. By 1245, several of the crew were experiencing headaches, fatigue and severe nausea. This was attributed by various members of the crew to either seasickness, a reaction to the food eaten at lunch, or the presence of exhaust gas in the accommodation. None were aware they were actually suffering from fumigation poisoning.

With the exception of the chief engineer, who went to the engine room, the affected crew either remained in their cabins, or went to the bridge or on to the boat deck to get fresh air. At about 1800 that day, when the master became aware that at least three of the crew were unwell, the possibility of fumigation poisoning was raised.

The atmosphere in the accommodation was re-tested and the presence of deadly fumigation gas was confirmed. Local authorities were immediately informed of the situation and assistance was requested. The crew were then moved to the ship’s office and master’s cabin, where windows could be opened to increase the flow of fresh air. Some time before 1900, one crew member returned to his cabin unnoticed.

About one hour later, a rescue helicopter arrived at the vessel. A winchman was lowered onto the deck, but poor weather conditions and a technical issue with the helicopter meant the helicopter had to return to base without the winchman or affected crew. The vessel re-routed to the closest port.

By now, three members of the crew were in a serious condition and the crew member who had returned to his cabin was found there unresponsive.

An hour later, a second helicopter arrived with a medical team. They were able to stabilise the three crew, who were evacuated by boat when the vessel approached the port pilot station. They eventually recovered in hospital. The unresponsive crew member was declared deceased.

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Investigation findings

The official investigation found, among other things, that:

  • No consideration was given to the potential knock-on effects of closing the ventilation flaps of the accommodation, thus stopping the ventilation, or the additional risk posed by the fumigated cargo.
  • By the time the vessel accommodation’s forced ventilation was stopped, there was a positive pressure of fumigation gas in the hold. Stopping the ventilation and closing the ventilation flaps resulted in positive pressure being lost in the accommodation, allowing the fumigant to enter the accommodation via the sanitary ventilation system and, to a lesser extent, other entry points.
  • At least two members of the seven person crew (28%) were not present for the Chief Officer’s fumigation briefing. It would appear that the briefing did not highlight the risks of the operation or symptoms of poisoning enough to alert the crew when taken ill, even for those that were present.
  • The periodic monitoring of the accommodation and engine room atmosphere was not conducted at the required eight hour frequency and did not detect the fumigant in time to avert lethal levels of exposure. Additionally, the fumigant’s ‘carbide additive’ did not provide sufficient olfactory warning (smell) to indicate the presence of the fumigant.

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Advice from The Nautical Institute

  • The suitability of a vessel for fumigation is a critical factor and could mean the difference between life or death. This problem has been seen in the past, as in Mars Report 200880, and in particular in the following Mars report 202210. Companies must have adequate procedures in place to assess the suitability of a vessel to carry fumigated cargoes.
  • The BMA report on which this MARS report is based lists seven other instances where fumigation gases have caused fatalities or very serious illness to crew (2008-2020). The common factors from these occurrences were:
    – Crew unaware of effects of exposure to fumigant gas.
    – Symptoms were confused with food poisoning or seasickness.
    – Ineffective or inadequate periodic testing regime.
    – Lack of effective physical barriers between fumigated cargo space and accommodation.
  • When in-transit fumigation of cargo is planned, extreme care should be taken to assess the integrity of ventilation trunks, shared bulkheads, duct keels and electrical conduits that might allow passage of gas into accommodation or working areas.
  • Masters and crew of vessels used for in-transit fumigation must be aware of the potential impacts of changing ventilation arrangements such as adjusting closing devices or flap settings, air conditioning and closed loop ventilation; this could create a vacuum which draws in the fumigant gas.
  • Periodic atmosphere monitoring is not as effective as continuous monitoring.
  • All crew must be fully aware of the risks and mitigation measures required to carry fumigated cargo safely. All should be fully briefed on the particulars of the smell of the fumigant, effects of poisoning and actions to take if exposed.

Mars Reports

This accident was covered in the Mars Reports, originally published as Mars 202209, that are part of Report Number 353. A selection of this Report was also published in SWZ|Maritime’s April 2022 issue. The Nautical Institute compiles these reports to help prevent maritime accidents. That is why they are also published on SWZ|Maritime’s website.

More reports are needed to keep the scheme interesting and informative. All reports are read only by the Mars coordinator and are treated in the strictest confidence. To submit a report, please use the Mars report form.