USRider Advises Steps Avoid CO Poisoning in Horse Trailer Living Quarters

Two children and their grandparents were killed by carbon monoxide fumes while sleeping inside the living quarters of a horse trailer the night of Oct. 11 (for more on this see They were in Madison, Wis., for the World Clydesdale Show. The family ran a well-known Clydesdale operation in Tomah.

Carbon monoxide (CO) is a potentially deadly gas produced any time a carbon-based fuel, such as gasoline, propane, charcoal, or oil, burns. Sources can include gasoline engines, generators, cooking ranges and space heaters. Carbon monoxide is undetectable--it has no color, no odor, and no taste; it causes no respiratory irritation, and it mixes evenly with the air.

The trailer involved in this accident was not equipped with a heater, so the Tomah couple used a propane heater to warm the sleeping quarters. A roof vent was open in the trailer, but it did not provide sufficient ventilation because CO gas hangs low to the ground--it does not rise like heat. The lethal level of carbon monoxide killed the campers in their sleep.

The horses were not in the trailer.

Victims of CO poisoning are usually not aware they are being exposed to the deadly gas and become impaired in ways that can lead to death. Symptoms of carbon monoxide poisoning include light-headedness, dizziness, headaches, nausea, confusion, and vomiting. Prolonged exposure to low concentrations or very short exposure to high concentrations of the gas can lead to death.

To avoid CO poisoning, horse owners sleeping in trailers should be aware of the risks, ensure sufficient ventilation, properly install and maintain equipment, and utilize carbon monoxide detectors, especially in living and sleeping areas.

"We do not recommend any type of heating system to be used in horse trailers, unless the heater is one that was installed by the manufacturer," said Mark Cole, managing member of USRider, a roadside assistance plan designed for horse owners. "Additionally, factory-installed heating systems should be serviced annually by a professional and operated strictly under recommendations of the heater manufacturer."

While it might be tempting to use a stove--if the trailer is equipped with one--for temporary heat, they should not be used for that purpose under any circumstances, Cole said.

Cole also recommended that a CO detector be installed in any trailer that has gas appliances, such as a heater, stove, oven, or refrigerator. The detector should be maintained as recommended by the manufacturer to ensure that it is performing as designed.

For more information about USRider and more equine trailer safety tips, visit the USRider Web site at

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