Southland businessman's boat death linked to generator fumes

An Invercargill businessman died from carbon monoxide poisoning while on a boat trip, a coroner has ruled.

Richard Charles Murrell, 60, was sleeping on his boat, Fishin’ On, at Lake Manapouri on July 19 last year.

• Tributes flow after Lake Manapouri death

The boat was found by police on July 21 and Mr Murrell was dead, and further investigation found a generator and diesel heater were being used aboard.

His friend Scott Allison was found confused and unwell, but survived.

Coroner Heather McKenzie last month ruled carbon monoxide toxicity, exacerbated by his heart disease and alcohol use, caused Mr Murrell’s death.

On July 19, Mr Murrell and Mr Allison set off on their trip.

They planned to travel from Lake Manapouri Boat Club and stay at the Freeman Hut.

But when they arrived, there were already people at the hut, so the pair decided to sleep on the boat.

The coroner noted they had never done this before, but had done plenty of overnight trips staying in huts.

A new diesel heater had been installed on the boat two days prior.

They cooked dinner using a portable grill and used a petrol generator to power Starlink (used to connect to internet via satellites) so they could stream a rugby game.

The diesel heater was running but they turned it off before going to bed between 10pm and 10.30pm.

But sometime later Mr Murrell turned the heater back on.

“The next thing Mr Allison remembers is a man, now known to have been from the Fiordland Marine Search and Rescue Team, banging on the boat telling him to get onto the deck,” the coroner’s decision said.

“Mr Allison felt very groggy but managed to get up and tried to revive Mr Murrell but could not.”

Mr Allison’s wife had called police when her husband did not return home on the afternoon of July 20 as expected.

At about 1am on July 21, a rescue helicopter crew found the boat in Safe Cove.

Mr Allison was taken to Southland Hospital.

The boat was later taken to Manapouri by police where Mr Murrell's body was recovered and the generator was found switched on and empty.

A post-mortem examination found Mr Murrell died from carbon monoxide toxicity - although the levels in blood would not usually be fatal.

The forensic pathologist explained Mr Murrell’s heart disease and the alcohol in his system made him more susceptible to carbon monoxide poisoning.

A police investigation found exhaust fumes from the generator travelled into the cabin where the men were sleeping via a hole for wires.

“Testing indicated that the diesel heater did not contribute substantially to carbon monoxide levels inside the cabin,” the decision said.

Maritime New Zealand said testing results indicated using the diesel heater might have created a vacuum that drew in air from outside the cabin to replace the internal cabin air. 

“This was on the basis that simultaneously running the diesel heater and the petrol generator on the deck combined to produce fatal [carbon monoxide] levels within 3.5 hours,” the decision said.

“Running the diesel heater only or the petrol generator only did not significantly increase [carbon monoxide] levels.”

Although they were not required, Maritime NZ recommended the installation of carbon monoxide detectors on vessels with enclosed accommodation spaces and diesel heaters.

It also suggested education around the dangers of carbon monoxide emissions from generators on vessels and “installers of diesel heaters should be aware of possible dangers of operating a diesel heater at the same time as a fuel burning device such as a portable generator”.

The coroner endorsed Maritime NZ's recommendations.