The FireAngel Carbon Monoxide alerts you to the danger of carbon monoxide poisoning in your home through your boiler or other fossil fuel burning device. Our tester, like most of us, had heard of the dangers and had been meaning to do something about it. The FireAngel is easy to set up and lasts for seven years. Seven years of peace of mind and safety from otherwise undetectable poisonous gas. At Spring Chicken we think it is just as important to fit a carbon monoxide detector as it is to fit a smoke alarm.