As far as fire extinguishers, it's required for Jet Jocks, but I don't think it's a requirement for glow/electric. All told I've been playing around with glow engines 4+ years, boats/cars/airplanes, and have never seen an engine ignite fuel outside the combustion chamber. Worst I ever saw was a guy smoking while he refueled his car from a spout, scorched off his eyebrows and nose hairs and burnt up all the plastic parts of his car.

But I ALWAYS carry an extinguisher in the car.....