Honestly, it doesn't hurt to be safe, tape a bag over it as some said or try this method, get a cardboard roll in the rolls of toilet paper and fill it with those sheets you shove into dryers to prevent static from having the things cling together (name escapes me at the moment) and fill it to the brim with multiple layers, it'll act as a filter of sorts to catch the smoke, be warned, I've tried this once, its a hit and miss thing, be prepared for the worse.