Even if having a smoke and carbon monoxide (CO) detector in every bedroom and hallway wasn’t a good idea in and of itself, many building codes now require it for new construction. Of course, fire is usually an obvious danger, but carbon monoxide is a silent killer—an invisible, tasteless, and odorless threat that sickens tens of thousands of people every year. Or worse. Fortunately, many modern smoke detectors are integrated with on-board CO detection, making it easy to protect your property and family from both hazards with one unit. Here are a few different options to consider, each with their own best-use application.