If you perform an Internet search for boiler accidents, you would find page after page of shocking stories and pictures. All these images and stories make the unknowing public wary of boilers, thinking they are dangerous. However, I believe heating with boilers is one of the safest methods.
People have much higher odds of being exposed to carbon monoxide from a malfunctioning oven than being the victim of a boiler accident. In fact, the Centers for Disease Control and Prevention says unintentional carbon monoxide poisoning caused an average of 430 deaths per year during the 1999-2010 period.