A portable generator can be a real lifesaver during a power outage. It can also be a killer if it’s not used correctly.

These machines pose risks such as electric shock and fire, but the largest risk, and the one that causes the most deaths, is carbon monoxide (CO) poisoning. In fact, portable generators caused 931 deaths from CO poisoning between 1999 and 2012. Not surprisingly, the number of deaths rises in years when there is severe weather.

To avoid injury and even death from a portable generator, it’s crucial to use it outside your home, never inside. That means outside of your garage, too. You also need to keep the generator at least 20 feet away from windows, doors and vents.

If you have a portable generator — and even if you don’t —it’s crucial to install battery-operated CO detectors in the hallways of your home outside of all bedrooms. Because carbon monoxide is colorless and odorless, it’s impossible to know without an alarm if it’s in your home until you start experiencing symptoms of CO poisoning.

Some of the symptoms include headache, weakness and shortness of breath. These can quickly progress to mental confusion and loss of consciousness.

If you suspect CO poisoning you need to get out of the house immediately, call 911 and go to the emergency room.

See the other tips for operating your generator safely here.

carbon monoxide infographic 

(Photo: CPSC) 

This infographic originally appeared here.

Sydney Herwig is an Associate Editor/Producer for SafeBee.