I'm sure you know how this works. But since we're having this friendly discussion on a public forum, I thought it might be educational for those who don't.
I'll look over John Freeman's booklet in more detail later. In my quick read, he's reputing claims that fabrics can be effectively 'fire-proof' and he says that if the whole
stage area is burning up, the
curtains will burn too, so the claim of 'flameproof' and 'fireproof' is false. In his analysis, he writes (pdf p. 55) "the best we can hope to accomplish is to 'flameproof' a fabric so that it will not ignite from a match, an
electric spark, or a gas jet; or so that if ignited it will not burst into flame." Which is exactly what flame retardants do! They do not, and do not claim to make
curtains 'not burn'. They make the fabrics and
curtains not be the main contributor of turning a little fire into a big fire.
He even develops a hand-held version of his fire test for fabrics to be employed by fire inspectors and others to verify the requirements of the 'new NYC building code', which is pretty cool.
In the past, the common term 'flameproofing' has been used, which is very misleading. I and others consciously use the term flame retardant, not "-proof".
I'll read the booklet in more detail, and I want to try to recreate his stove-pipe experiments; more later. In the meantime, I'll
stand by the use of flame retardants as being effective at what they are designed and employed to do - which is to retard the spread of fire on the treated fabric.
I thought electrical shorts and
pyro were the leading contributors to "starting" fires on
stage? Just my impression. I'm not aware of a compilation or detailed study.
https://en.wikipedia.org/wiki/List_of_nightclub_fires for some general info, not thorough nor complete?