I've used a 23,000 BTU round model in my smoke detector equipped basement and garage for 15 years.
- I turn it off and let it cool (or remove it) before using volatile stuff. - I take it out of the basement (walk-out, no stairs) to start it and turn it off. This keeps the smell out of the house. I don't bother in the garage. - Every 2-3 tanks, I "dry burn" it to clean the wick. - I use my Jet AFS-1000B to even the heat distribution - I never leave it unattended
Works great for me. My wife is SUPER sensitive to odors, and she doesn't complain. <G>