Burn Proof? Not...
Don't forget boys and girls, your expensive NOMEX suit is no longer fire retardant and therefore an utter waste of time as such, if you don't launder it correctly.
If you wash your NOMEX suit in a machine with all your other laundry, made up of the usual garments made from cotton, wool and other various man-made fibers, the fibers from those clothes will entwine themselves amongst the cloth of the NOMEX suit, thereby reducing it's fire retardant qualities substantially. It is even worse if you've put the flight suit in a tumble dryer with the same other items of clothing mentioned.
When I was in the Air Force (guess which one?) Safety Equipment Section was responsible for laundering our issued flight suits. We were not supposed to launder them ourselves - ever. The washing machines Safety Equipment used had only ever had NOMEX type material in them, and a specific flame retardant detergent was used.
Away from the training base though, it was a different story...
Besides, a properly laundered NOMEX Suit is only good for protection from a flash fire. A fully established post crash fuel fire and you're probably a crispy critter anyway.
However, given a choice, I'd rather wear a flight suit over the faggy looking blank pants/white shirt and airline-wanna-be-captain-bars-moneky-suit, so many companies insist we wear. Just a personal thing. To each their own I guess...
For example, there's nothing like the red grease from a Bell preflight on your spiffy looking white shirt to make you look - well nasty and unprofessional. On a flight suit, chances are it can be a bit less conspicuous.
Maybe that's why there are several companies out there, that seem to insist that the pilot preflight of a helicopter is, merely a "walk around", with no getting up there and into it with the cowlings open - to really look it over.
Besides all that "personal preference" regarding uniforms goes though, the main thing I'd like to point out is that I have several personal mates, several acquaintances and even more "anecdotal colleagues" who are alive today, due to the fact they were wearing a helmet when things got nasty.
Which is why I insist on wearing one myself - always.
In fact the last 3 jobs I've had, I have asked during the interview process if there was any issue with my doing so. Luckily, I was told, "No, that would be my personal choice." When asked why I had asked, I said that if the answer had been "No", I would have had to pass on the job.
As someone previously said, it's often pretty hot in there anyway, even with just a lightweight headset. So the peace of mind the added protection gives is well worth it. The plus factor I find is the huge reduction in noise I have from the helmet I wear, and the added safety from the clear visor I always have down, no matter the weather or light conditions.
There'd be no worse of an irony I think, of being alive after the impact of the crash, but non-compus-mentus enough to fail to make it out of the wreckage due to the fact you were stunned from a head impact, and then end up burning or drowning after the fact. That would just seem dumb and futile to me...
So, at the end of the day, here's wishing you all safe flying, good luck and never the need to require the necessity of the safety equipment we are advised to use.
A safe and prosperous 2009 to you all! Take care...