When fossil fuels — e.g., gas, oil, wood and coal — burn or combust, they produce carbon monoxide (CO), a toxic gas that can be deadly in high concentrations. Although you cannot see it, smell it or taste it, carbon monoxide can find you. Because of this undetectable, almost stealthy quality, CO is a threat to all of us.    
 
How does CO enter your home and how can you protect yourself? This poisonous gas can escape from any appliance or mechanism that runs on fossil fuels, such as a fireplace, stove, furnace, or wall heater — even the car in your garage. Common sense would dictate that you keep these appliances in good condition and the areas where they operate well ventilated. Note that while newer homes may have safer appliances, these buildings are also better sealed and insulated to trap potentially dangerous CO indoors. The cold weather months also offer a greater chance for CO exposure because of increased furnace and fireplace use.

To best protect yourself, simply buy a low-level CO detector and install it according to the manufacturer's guidelines in your home. In fact, residential CO detectors, like smoke alarms, are required by law in many states, though not yet in California. Depending on the size of your home and whether or not it has a fireplace, you might need more than one detector. These devices are not expensive and are easy to install, but having and maintaining one is the most crucial step you can take to prevent CO poisoning or its other effects. If your CO alarm ever sounds — or if you smell gas in your home — evacuate the premises immediately, leave the doors and windows open for ventilation, and call 911 from a remote location.