NEW YORK, (REUTERS) — After a flood, people run the risk of carbon monoxide poisoning if they operate gasoline-powered equipment inside their homes, a new report shows.

Carbon monoxide is a colourless, odourless gas produced by the incomplete combustion of fossil fuels. Exposure to the gas interferes with the body’s ability to use oxygen, and can be fatal.

The report, published in the November issue of The Journal of Emergency Medicine, describes a rash of carbon monoxide poisonings that occurred in 1997 after a severe flood in Grand Forks, North Dakota.

Eighteen separate incidents caused 33 cases of carbon monoxide poisoning, according to Dr W Randolph Daley of the US Centres for Disease Control’s National Centre for Environmental Health in Bismarck, North Dakota, and colleagues.

The patients, between the ages of six to 67, reported one or more of the symptoms of carbon monoxide poisoning, which include headache, dizziness and nausea.

All of the poisonings occurred while gas-powered pressure washers were being used to clean flood-damaged basements. Basements often collect mud and debris left by floodwaters.

The pressure washer engine had been placed inside the basement or stairwell in each incident, and most patients reported that the basements were ventilated.

Daley and colleagues note that gasoline-powered equipment is often needed in flooded homes to provide electricity and help clean up damage.

In the case of power washers, the researchers suggest that warnings are needed that “clearly state that the engine component must be operated outside and away from any location where exhaust could vent into a building” .

Carbon monoxide poisoning from gas-powered electric generators and other equipment is a growing problem, especially after floods, storms and other disasters, the report indicates. “Prompt community awareness campaigns in flood-impacted areas can prevent future outbreaks,” Daley’s team concludes.