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A house fire now gives you minutes, where it once gave you a quarter of an hour
Furnishings changed faster than habits did. Solid wood, cotton, wool and horsehair have largely been replaced by polyurethane foam, laminates and synthetic textiles, which release far more heat far faster once they are alight. Fire research laboratories that burn a room furnished the way rooms were furnished in the 1970s beside a room furnished the way rooms are furnished today report the modern room reaching flashover, the moment everything in it ignites at once, in around three minutes, against roughly seventeen for the older room.
That single change explains why this site is organised the way it is. If the warning arrives late there is no time left to improvise, so the two things that decide the outcome are an alarm that is actually working and a way out that was decided before anyone needed it. Equipment matters, but it matters in that order.