Here's how you can avoid carbon monoxide poisoning as the temperature drops

Emergency calls related to carbon monoxide poisoning increase during the winter, especially when people try to boost indoor heating during a cold snap. That might mean burning wood beneath a chimney you haven't cleaned recently, lighting a kerosene lantern or using a gas stove to warm a kitchen. If the power goes out, some people fire-up gas-powered generators in their basement or garage.

All of these unventilated heating methods increase your risk of carbon monoxide poisoning.

Early symptoms can include a headache or fatigue, according to Dr. Powell Graham, a medical toxicologist at the UMass Chan School of Medicine

"As they progress [the poisoning] can cause things like chest pain and confusion, seizure and dizziness," he said. "Ultimately people can lose consciousness or die."

Graham said effects that are not severe at the time can still cause long term brain and nerve damage. More than 100,000 emergency room visits every year are for CO-related injuries, according to the Centers for Disease Control and Prevention. Of those, about 14,000 patients need to be hospitalized and more than 400 die.

"The true danger of carbon monoxide is that it’s completely invisible, odorless, tasteless and it doesn’t irritate you," said Graham. "So there’s really no way to detect it without a carbon monoxide detector."

The CDC recommends installing battery operated CO carbon detectors in homes, especially near sleeping areas, and changing the batteries twice a year when you adjust clocks to spring forward or fall back an hour.

The CDC also recommends keeping generators 20 feet away from your home while running to avoid CO leaking in through doors or windows.