[n2_space]

I have used a 40K BTU propane torpedo type like you showed for two years when I detail in the garage in the winter, never had any problems. I just keep it away from everything, park the car in teh middle of the garage, put it about halfway in the garage, half way between the wall and car, and nothing is in front or back of it. I can keep my door open and based on two thermometers in the garage, it never drops temp wise. I only run it like that though, when I detail, with the door open. Works out great for me.