According to the Scripps Howard news service, cold weather means people are using their heaters and furnaces more, and keeping their houses closed up perfect conditions for carbon monoxide poisoning-- What exactly is carbon monoxide? It's an invisible, odorless, tasteless gas. It's created when natural gas, charcoal or wood is burned. You can also get it from common household appliances, like furnaces, water heaters, clothes dryers, space heaters, and ovens. At low levels, healthy people feel fatigued. High levels can cause blurry vision, headaches, nausea, dizziness, confusion and even death-- To prevent carbon monoxide poisoning, you've gotta have good ventilation. So, here are some tips on how to keep safe: Don't leave the rear window of your SUV, van or camper open when you drive--Exhaust fumes can get sucked right in. So, crack a front window, instead-- Once a year, have your heating and ventilation systems inspected, including chimneys and flues-- Look at the color of the gas flame on your stove or water heater. A hot blue flame produces less carbon monoxide and more heat than a flickering yellow flame. If it's yellow, the equipment needs to be readjusted-- Also, don't burn charcoal inside, even in a fireplace.And finally, never use any gas heaters that aren't vented to the outside, especially in bedrooms-- But the best way to keep from being poisoned in your own home is to get a carbon monoxide detector. It works like a smoke alarm, and warns if the carbon monoxide levels get dangerously high.