I dont know yet if it works or not.

I have used the Mr Heater in a Pop Up camper with no problems BUT before I bought it I researched it carefully On a LOT of RV Forums and a Lot of people use them and the consensus is as long as there is 8 to 10 square inches of ventilation (preferably cross ventilation) there is no need to worry.
Some people shut it off when they are sleeping and some dont.

Faster horses,Younger women,Older Whiskey,More money