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EN 12845, NFPA 13

Design density

Water application rate per unit area, expressed in mm/min (metric) or gpm/ft² (imperial).

Definition

Design density is the core hydraulic specification for any sprinkler system. EN 12845 defines it by hazard class; NFPA 13 by the density/area curve in Chapter 11. The most demanding sprinkler in the most remote area must deliver at least this density at its design pressure.

Referenced in

  • EN 12845
  • NFPA 13

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