Question

Why is it not advisable to sleep in room with coal fire?

Answer 1

due to burning of coal harmful gases such as Carbon monoxide is released
And if the room will be close the room will be full of carbon monoxide and person in the room will unable to inhale. Due to which there is a possibility of death...
That's why it is advised not to sleep in room with coal fire.

Answer 2

It is advisable not to sleep in a room with coal fire because for the combustion of coal, oxygen is necessary. It takes oxygen from the air in the room and makes us suffocated . Also the fumes produced on burning is hazardous .
Hope it helps u.