A few people know that I will not allow naked flames inside my tents, to the extend of being loudly and rudely afraid of flame under nylon / canvas.
The reason for this is nylon burns. Nylon burns quickly.
The average time for a cheap nylon tent to go up completely according to Greater Manchester Fire and Rescue service is 8 seconds. I watched this happen as a 14 year old. The fire spreads at incredible speed
Except nylon does not burn completely.
So as your tent goes up, it drips melting, burning nylon onto the people inside it.
I quote the firemen on the RAF station who were demonstrating this to me. "The lucky people die at this point. The unlucky people get to live with all this stuck to their skin". Memories of this are why I do not allow flames in my tents.
The most obvious thing to take away is not to cook or have naked flames inside your tent.
The next thing for the purposes of fest larp is making sure there is a suitable break between your tent and the ones next to it. It's a courtesy thing for one to give people ample room to deploy extra guy ropes or walk between the tents, it is also a safety issue - creating a fire break so that one burning tent will not set them all going. As I have learned the hard way, it is often good to deploy all your guys immediately as a way of claiming personal space to stop someone putting their tent right up next to yours.