The sudden shift in cold weather has many New Jerseyans turning on the heat in their homes for the first time this season. That may be putting them at risk for carbon monoxide poisoning if heating systems have not been properly serviced.

Bruce Ruck, managing director at the New Jersey Poison Center at Rutgers in Newark, says the problem is if the heating system has not been used in a while, the flues and chimneys get clogged with debris from the previous year. As a result, gases can't escape.

As winter progresses, he says snow will get into chimneys, vents and pipes from washing machines and dryers, allowing carbon monoxide to build up.

In recent weeks, the NJ Poison Center has received up to a dozen calls about carbon monoxide poisoning. Last week, 11 residents in an apartment building in Jersey City became ill from CO poisoning. Several of them needed hyperbaric oxygen therapy at hospitals in New Jersey and New York.

Carbon monoxide is called the "silent killer" because it's colorless, odorless and tasteless, but quite deadly.

Ruck says exposure to CO can lead to headaches, tiredness, drowsiness, dizziness and light-headedness. At higher levels, nausea, vomiting, irregular heartbeat, impaired vision and coordination are very common. The symptoms of CO poisoning are similar to the flu without the fever.

Ruck says carbon monoxide detectors should be installed in every level of the home. Some people will put one in every bedroom or immediately outside. You should also install a detector near the furnace in your home.

But one thing he wants to make clear: the answer to a carbon monoxide alarm going off is not pulling out the battery. "If it's chirping and it's the battery, absolutely replace the battery. But if that alarm continues to go off, you need to have your house checked by either the fire department or gas company," says Ruck.

To reduce your risk of CO exposure or poisoning, Ruck says it's important to keep the heating and dryer vents in your home clear of all debris. Open flues when fireplaces are in use. Gas appliances must have adequate ventilation, so keep a window slightly cracked to allow airflow. Never leave your car running in the garage with the door closed.

Ruck also says "if you find you're without power and you have to use a portable generator, you are to make sure that generator is far away from the house, at least 20-25 feet away."

If you suspect carbon monoxide poisoning, you must take immediate action. Ruck says the first thing you should do is get the person out of the house and into fresh air. If the person is unconscious or unresponsive, he says call 911. If the person is awake but there is obviously something wrong, he suggests calling the New Jersey Poison Center at Rutgers at 1-800-222-1222. It's free and the center covers the entire state.

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