Polypropylene under ware-BEWARE!
I have mentioned this in other topics- That synthetic materials MELT when they burn, and cause WAY worse burns than if natural fibers had been used!
A close friend of mine just learned this the (very) hard way.
He operates an auto/misc upholstery shop in a small town on the wet side of Washington.
His shop is (was?) small, but too big and poorly insulated to try to heat the whole building, so he used radiant space heaters. He used both small electric and larger propane depending on the application. Evidently the short propane hose from the tank to the radiant heater leaked and formed a low layer of propane in the shop and then ignited. He was Inside working when it happened.
UNFORTUNATELY he was wearing polypro long john bottoms under his denim jeans. When the gas ignited/exploded/'woofed' it also ignited the long johns he was wearing and they started burning and melting UNDER his jeans-which were singed, but maintained their integrity.
If he would have had cotton long johns he would have just suffered the burns to his hands, face, eyes, and ears-which is plenty bad enough. BUT, because of the polypro he ALSO has 2nd and 3rd degree burns to his legs. He will be having skin grafting surgery on Mon or Tues and maybe supplemental surgeries later depending on healing. He will be in the hospital at least 2 weeks, likely more.
In Iraq, we (good guys) learned some hard/fatal lessons about synthetic fibers and the damage they can cause when they meet flame or soon to be ignited flammable vapors. Moderate survivable AIRCRAFT impacts that released and vaporized fuel-when ignited would turn the pilots/passengers into crispy critters if they were decked out in polypro/synthetics. The plastic cloth melts and STICKS to you-and cannot be taken off or rubbed off without taking the SKIN with it!
DO NOT wear it under Nomex and think you are protected! In certain situations it can burn and melt UNDER the Nomex-just like under his jeans. Think of all the Polly coats, tents, shirts, fleece, socks etc as the OPPOSITE OF NOMEX. It loves to burn and melt and drip.
Cotton, wool, bamboo, WHATEVER! Natural fibers will burn, but it ignites at a higher temp and does NOT melt to you.
Pilots and friends: Please read, and re-read, and internalize-and ACT on-this information. For you, and you family/passengers.
There are a lot of "me"s out there-as in-It wasn't going to happen to "me"!