Fire sprinklers you ask? For what kinds of buildings does code mandate them for? Generally, you can say that fire sprinklers are not mandated for buildings, but the kinds of buildings they appear in are generally factories, office buildings,
Interestingly, fire sprinklers were around for a long time, since the early 1800s, but a long-standing problem in adoption was their cost. So, the way to get adoption moving forward among customers was to work with insurance companies to have the fire sprinkler system installed in exchange for a reduction in insurance premiums.
20180825/https://en.wikipedia.org/wiki/Fire_sprinkler
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