Carbon monoxide. It's the silent killer, claiming an average of 430 lives each year in the United States. If you do not want yourself or any of your family members to be among those 430, then it's important to be vigilant. Sadly, a tiny mistake can lead to carbon monoxide poisoning. Here's a look at some could-be-deadly mistakes to avoid.

Not testing your CO detector.

Your CO detector should start beeping when the battery is low. But like all machines, it could malfunction. Do not rely on this beeping alone to tell you if the detector is working. Push the "test" button once a month to ensure your CO detector is still functional. Also, change the batteries once a year whether or not the device tells you they're drained. If you look at the back of you detector, it probably has a date after which it should be replaced. Adhere to this by purchasing a new CO detector once that date approaches.

Fixing your furnace yourself.

Your furnace is an intricate system. If the burner is not adjusted properly or the vent pipes are not sealed the right way, it's really easy for CO to leak into your home as it is generated. HVAC contractors spend several years in school and apprenticeships learning how to safely repair and adjust furnaces. Don't assume you can learn to do this yourself in the span of a few YouTube videos. Always hire a professional with a good track record to repair your furnace. It's better to pay a few hundred dollars than to pay with your life.

Putting a generator too close to your home.

A portable generator can come in handy when the power goes out. Putting it outside rather than inside is a no-brainer since it burns fuel and therefore gives off CO. But just putting it outside is not good enough. If you place it too close to your home, the fumes could leak in through a window or door. Experts recommend putting your generator at least 25 feet from your home. Try to place the generator so the prevailing winds carry emissions away from your home rather than towards it.

CO poisoning is a serious matter. Even if you do not die from exposure, you could develop severe nausea, confusion, and headaches. If you suspect CO poisoning, get out of your home and seek medical care immediately. Do not return until an HVAC technician or home inspector has looked over your building and determined that it's safe.