I wear a nomex flight suit when flying ex-Military aircraft or when engaged in specialty operations like forest fire fighting. I do not wear a fire resistant suit for your average Piper/Cessna flight as I think the risk is low enough that I am comfortable in regular clothes.
However as Genghis says it is your decision. I would say that you should put it on when you get into the airplane and take it off when you get out. Wearing it around the flying club will invite (deserved IMO) ridicule. I would also say that IMO in the context of normal GA flying 80 % of the value of a full suit can be achieved simply by wearing a set of Nomex back/leather palm gloves. Protecting your hands will allow you to touch a hot switch/control/structure which could make the difference in fighting a cockpit fire or mean the difference of escaping or being trapped in a crashed burning airplane. In the meantime it gives you a good grip when your hands are sweaty.
I would also ask an open ended question. Are you doing everything you could to avoid the accident in the first place? That is do you follow a regular program of recurrent training, practice checklist discipline, understand the aircraft systems, study the safety bulletins and learn what not to do by studying accident reports etc etc etc. Those are IMO the areas where true improvements in flight safety occur, not wearing a nomex suit to fly your Pa 28 for a local bimble.....
Last edited by Big Pistons Forever; 31st Jul 2012 at 21:11.