I use it in my tent, it is good for a blast of heat. I wouldn't leave it running for extended periods of time. It is not safe to run while you are sleeping, and you don't leave it - not even while you leave the tent for a second.
Fume build up would be my main concern which is why I only use them to take the edge off the chill and then turn it off again.
Electric hook up and a small fan heater is the only viable alternative.
I use my heater. I do a lot of winter camping recently. I'm not going to freeze my butt when I'm getting change. Just be sensible.
------------- New Year: Hesketh Bank
Feb/March: Red Squirrel
March: lakes
June: Morecambe
Aug: Lake District(not camping camping)
October: Red Squirrel
If the op needs to ask then then answer would have to be no. If anybody cannot work out for themselves how to safely use a gas fire in a tent just looking logically at the overall picture then they should not do so.
I suppose sensible advice would be to use heater only while awake & don't go to sleep with it on. This of course assumes camper does not just drop off to sleep with heater on so perhaps advise camper not to use heater while lying down!
What is for certain is that this thread will go the same way as any other similar thread on this forum & the op will be no further forward at the end of it.
A point to mention about the heater linked to by HB. It uses butane cartridges so if you try to use it after a freezing night in one's tent it will not work as butane does not work in cold temps as mentioned in some of the reviews.