London banned coal fires in the 1800's. English descendents still put dressers and bureaus in front of windows from tradition to keep out the unhealthy carbon-0monoxide-filled night air. Towns in New Hampshire, Oregon, and Canada have banned wood fires because of pollution (wood fires are the least efficient form of combustion.)
The hot air that lifts the ash and products of combustion cools and drops to the ground with the heavy ash. People died early when the form of heat was wood fires - pneumonia reigned.