When I began my career in 1987, NFPA 13 and its “Standard for the Installation of Sprinkler Systems” was an easy document to use.
There were three basic types of sprinklers and two orifice sizes used for almost all systems except deluge. Most buildings fell into one of three occupancy classifications, regardless of what was stored. Other NFPA standards applied to warehouses with large general storage, rack storage and tires. Plastics were less prevalent and most everything was Class I, II, III or IV.