I bought this item to be used in a campervan. I haven't used it yet for that purpose but I have tried it at home. It wasn't working to start with, but it was only due to me not giving enough of a push when twisting the knob. When I did, it worked perfectly well and the heat was great for such a small device. I think no business would advertise to use them inside for H&S reasons, but I would say if you use it in a well ventilated area, and you don't leave it un attended, there should be no problem, especially because it is the only one I found that had a system to shut off when the level of oxygen is low. Great that it also stops when tilted.