last year two hunters died in Michiganfrom one mr. buddy heater. I would say yes only if you absolutly have to have it on. I only use one if it gets in single digits and then i keep all the windows open in my blind. If I even think im getting a headache i immediatly turn it off. this is during gun season of course. Im not saying that you shouldnt but just be extremely careful. I had a great uncle who died of carbon monoxide poisoning so im a little leery anyway.