here is a thought about toxicity of combustion products. Smoke and fire gases are nasty things, and it is best to make sure people are not exposed to them. But I suppose that's too simple?
...one of the fundamentals of fire safety, I'd say, but not always possible where the occupants and the fire share the same space. Personally I'd regard it as a bit of a red herring in most type of occupancy... what's the point in going to great lengths to control the properties of construction products knowing that the occupants will fill it with stuff that might be far more hazardous?
Railway infrastructure is a bit different - particularly tunnels and sub-surface stations - and is one of the places where the maintenance of low fire load (and control over the reaction-to-fire properties of the products installed) is reasonable and practicable (if slightly costly). All began after the King's Cross Fire and the Fennell Report.