Environment Canada issued a smog warning for Greater Montreal on Sunday night. If you live in the city of Montreal, that means you can't use your wood-burning stove or fireplace until the warning has been lifted, under a city bylaw.
Smog in Quebec is largely the result of wood-heating, which generates much more of the fine particles that create smog in winter than do industrial activity and transportation.
As a result of the poor air quality, it is also recommended that children with asthma and other people with respiratory issues, as well as heart disease, avoid outdoor physical activity until after Environment Canada has lifted the warning.