Carbon monoxide, often refereed to as the “silent killer,” has no taste, smell or color and as such is very difficult to detect unless you have a monitor or experience symptoms of carbon monoxide poisoning. While most people are aware that gas devices pose a risk, they may not realize that appliances fueled by coal, wood and oil can also produce carbon monoxide.
This infographic from MyBoilerService.com explains the seriousness of carbon monoxide poisoning and symptoms.