Jamestown, NY – Police are warning residents to use care as they turn on their furnaces to stave off the changing weather, as malfunctioning ventilation pipes can cause carbon monoxide to accumulate in the home.

Two elderly city residents recently fell victim to the poison, responsible for nearly 500 deaths and more than 15,000 emergency room visits each year.

They were exposed to high levels of carbon monoxide and sent to WCA Hospital for treatment.

Carbon monoxide — the leading cause of accidental poisoning deaths in the country — is colorless, odorless, tasteless and can cause permanent brain damage and death in high enough concentrations.

“We wanted to make people aware of this, because with the windows and doors all shut, in a confined space, it can happen very quickly when someone is overcome with carbon monoxide,’’ said Rex Rater, Jamestown Police Chief/Director of Public Safety.

Rater said the beginning of winter is a likely time for carbon monoxide poisonings, especially when many people have older furnaces that haven’t been recently serviced.

He urged residents to check the ventilation pipes of their furnaces and hot water heaters to see if they have become rusty or dislodged. Furnace repair companies recommend that older furnaces be serviced annually.

Carbon monoxide is produced any time organic fuel is burned. This includes wood, charcoal, propane, natural gas, gasoline and oil. In the home, common sources of carbon monoxide are non-electric furnaces, water heaters, ovens, stoves, fireplaces, grills, space heaters and clothes dryers.

Residents should make sure all these appliances — particularly their exhaust systems — are in good working order, and that fumes from the combustion are being vented outside.

Police also recommend that residents put at least one carbon monoxide detector on each level of their home. Detectors should be placed near sleeping quarters and should be loud enough to wake you up. Since carbon monoxide is lighter than air, detectors should be placed on a wall about five feet above the floor.

Symptoms of carbon monoxide poisoning include headache, dizziness, nausea and fatigue. Poisoning is often confused for a flu-like illness.

If you suspect a carbon monoxide leak, ventilate the house or get outside. If you are experiencing symptoms of carbon monoxide poisoning, go to the emergency room.

“If the threat is imminent and you don’t know who to call, call the fire department. If it’s during the day, call a reputable heating company or plumber,’’ Rater said.

Rater said there is no reason not to get regular furnace maintenance. In addition to preventing carbon monoxide poisoning, it can also save on heating costs.

“It’s absolutely a win-win situation,’’ Rater said.