Unventilated generator almost proves fatal

Lookout! Issue 36, December 2016

A Super 15 rugby final almost ended in tragedy for a crew member aboard a fishing charter boat berthed at an island off the coast of New Zealand.

The vessel’s main generator was not operational due to heat-exchanger problems. As an interim measure, the suitcase-style back-up generator had been placed in the engine room for use during the overnight charter trip. To avoid crimping the power cable, the hatch down from the wheelhouse was propped slightly ajar with a hammer.

The decision to use the engine room for the portable generator was prompted by the fact that two previous generators had suffered irreparable water damage when operating on deck. The skipper was also concerned that if the portable generator was outside the wheelhouse noise and fumes would affect the 17 onboard for the trip.

The charter group motored across from the mainland and fished at a bay on the island. They then tied up at the wharf and the whole party went ashore to a nearby hotel to watch the match, leaving only the skipper and a volunteer crew member aboard.

The pair found time for a bit of vacuuming before the match, which added to the loading on the generator. When the match started, the crew member was sent below to add fuel – to keep the generator going for the length of the game.

After a try was scored, the skipper called out to the crew member to let him know. Shortly afterwards he looked down into the engine room and saw the man lying next to the generator.

The skipper went down, turned off the generator, and found the crewman unconscious but breathing, with some foam around his mouth. The fuel container lid had been screwed back on, and the container returned to its storage position, but the fuel cap on the generator had not been replaced.

The skipper tried to lift the unconscious man up through the hatch but could not manage it. He started to feel dizzy himself. So he climbed out of the engine room and ran to a nearby boat for help. With the help of eight other men, they got the crewman up onto the foredeck.

Both skippers involved dialed 111 and the fire brigade arrived with oxygen. The crew member was taken ashore for treatment and subsequently flown by helicopter to hospital.

He was diagnosed with acid poisoning and carbon monoxide poisoning – with a highly elevated HbCO (carboxyhaemoglobin) level of 9 percent. The man discharged himself from hospital the next day and reported back to the vessel. However, he suffered headaches and fatigue for some time after the incident.

The skipper failed to report the incident immediately, as required by law. Instead he continued the charter trip, and booked ahead to have the main generator fixed on their return to the mainland. Since the incident, the back-up generator is now kept on deck again, sited so as to minimise the effects of sea and rainwater.


  • Most generators produce a lot of carbon monoxide (CO). CO is an odorless, invisible gas that can injure or kill very quickly.
  • It is vital to have a CO detector on any boat with a portable generator, or preferably two.
  • Portable generators should only be used in places where there is plenty of ventilation, and should be monitored closely.
  • The skipper should not have put to sea knowing that the main generator was unserviceable, and without taking all practicable steps to ensure his alternative arrangement was safe and fit-for-purpose.
  • In addition, the skipper did not provide any training or guidance in entering the enclosed space, where the unventilated engine had been running through-out the day.
  • A trained diver himself, he said that if he smelt fumes when refueling he held his breath for the time it took carry out the task. This means the skipper was already putting himself at risk that an accident or delay during refueling would have resulted in him breathing in the poisonous air.
  • Before entering a dangerous enclosed or confined space, it should be assessed by a person with sufficient knowledge and experience to ensure that the potential hazards of the space are identified and managed. Only enter the space if the risks have been effectively managed.
  • Entry work should not be done alone. A person should be assigned on safety standby for each entry. The person on standby should have the right equipment to be able to raise an emergency alarm.
  • If things go wrong, generally crew mates and others are advised not to rush in to carry out a rescue by themselves – even if they see someone lying motionless in an enclosed space.
  • Unplanned rescues can end in tragedy for all concerned. In this case, the skipper realized the generator needed to be turned off. But he should have opened the hatch for air and got help to carry out the rescue. Otherwise he might also have succumbed to the toxic gases – which could have resulted in two fatalities.

For more information about the hazards of enclosed and confined spaces check out:

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