Blunt warning for petrol engine boat owners

Published: Wednesday, 11 April 2018

AS WAS reported in narrowboatworld the last boating season saw four people killed by fumes from boat petrol engines.

In addition two others received emergency treatment after being also affected by carbon monoxide, which Marine Accident Investigation Branch investigations have shown can fill a boat’s interior with carbon monoxide in seconds.

Get out fast

The Boat Safety Scheme make the blunt warning that if you can smell petrol engine exhaust fumes in the boat, kill the engine(s) and get out fast before you inhale any further toxic fumes!

A major carbon monoxide (CO) risk comes from either big inboard petrol engines producing lethal volumes of the highly poisonous gas in seconds, or from outboards and other portable engines steadily increasing CO in the cabin; but whatever the source, the BSS warns that boaters cannot afford to drop their guard.

Gases drawn inside

Over the previous two boating seasons four people died and another two had emergency medical treatment when the cabins of their cruisers, with large inboard petrol engines, filled with a toxic cloud of CO as engine exhaust gases were drawn inside through the open flaps of cockpit covers, with Graham Watts, the BSS Manager explaining:

“The warning is targeted at owners of boats with large petrol engines and focuses on the risk when boat engines are run whilst the craft is moored.

"Investigations by the Marine Accident Investigation Branch (MAIB) have demonstrated how exhaust gases from petrol engines can flow back inside through slightly open flaps on cockpit covers. The gaps in the covers can act like a funnel to channel exhaust fumes into the covered cockpit area, and then fill the boat interior with a massive volume of CO in seconds.

"No amount of CO should be thought of as safe, even low concentrations over longer periods can cause long-term health problems. Good skippers will understand and control all risks to protect their crews. This includes knowing about CO and being able to recognise the symptoms of CO poisoning."

19 boaters died

Over the past 20 years 19 boaters have died and a further 21 were sent to hospital when CO in exhaust fumes from inboard, outboard and generator engines entered the boat. CO is a colourless and odourless gas, but when it is mixed with the other petrol engine exhaust gases that you can smell, you can be confident there is a risk you need to deal with immediately.

The symptoms of CO poisoning are similar to flu or food poisoning as the toxin begins to take effect, these include headaches, nausea and dizziness.

As time passes and, or the amount of CO builds, symptoms can worsen with chest pains and breathlessness and go on to seizure, unconscious. So the early recognition of the symptoms is critical, but if nothing is done, death can follow on quickly.
Because of circumstances where you may not smell the exhaust fumes, or you are asleep, it is critical to have a working certified CO alarm as the next line of defence.

Even if your batteries are desperate for a charge, don’t run an engine on a moored boat if the exhaust fumes are being drawn inside. Wait until the wind changes or move to a different mooring. And be a good neighbour and don’t run petrol engines where exhaust fumes could enter a nearby boat cabin.

These are the critical points

♦If you are smelling and breathing in petrol-engine exhaust fumes, stop the engine and get off the boat.
♦ Know the symptoms of CO poisoning, if anyone is indicating they are suffering, get them medical help. If the symptoms are severe – call the emergency services.
♦ As a belt & braces defence, have one or more certified CO alarms (BS EN 50291-2). They need testing routinely and never remove the batteries.