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People often turn on gas-powered generators, charcoal or gas grills, and propane devices when the power goes out after a storm hits. These can generate carbon monoxide, an invisible, odorless and lethal gas.
"If used or placed improperly, these sources can lead to carbon monoxide (CO) build up inside buildings, garages, or campers and poison the people and animals inside," the CDC said in a warning this week.
At least nine deaths tied to Hurricane Laura in Louisiana were from carbon monoxide poisoning, health officials said last month.
"These devices should never be used inside an enclosed space, home, basement, garage, or camper — or even outside near an open window or window air conditioner," the CDC said.
People are unlikely to be aware of the symptoms of carbon monoxide poisoning.
"A tension-type headache is the most common symptom of mild CO poisoning. Other common symptoms of CO poisoning are dizziness, weakness, drowsiness, upset stomach, vomiting, chest pain, and confusion," the CDC said.
If patients show such symptoms after a hurricane or another disaster, health care professionals should consider carbon monoxide poisoning, the CDC said. "Administer 100% oxygen until the patient is symptom-free or until a diagnosis of CO poisoning has been ruled out," the CDC said.