Yep when working way up off the ground,magnatised pipe and a little wind you can catch things on fire a long way away. Whats sad is how many people dont even think about fire and welding, I dont know how many times I have been up in the manlift welding looked down when changing rods to see someone filling it up with gas directly below me or setting a couple plastic full gas cans with no caps directly under where Im welding.
I guess the moral of the story is allways keep an eye out for what others are doing around you, might be safe one minute and explosive the next.
Here's a kinda funney one for ya, years ago my younger brother was helping me on a large dairy remodel job, I had to go to another dairy that day to do some repairs and left him there welding pipe trusses up, he was in the manlift about 20' up anyway he decided to take a brake, jumps in his subaru car goes to store and comes back parking his car next to manlift with windows open and the car is full of trash, dirty close ect. he goes up and starts welding, about 5 minutes latter the car goes up in flames so the **** hauler that working in the corral comes to the rescue with his loader and a full bucket of dirt, dumps it on the car and the flames go out. perfect the fire is out but the car is only about a foot tall with 4 flat tires!