Smooth-Bore Nozzle Flow (GPM)
The flow from a smooth-bore (solid-stream) nozzle: gpm = 29.7 x tip diameter^2 x sqrt(nozzle pressure), with the companion nozzle reaction 1.57 x d^2 x NP. Standard nozzle pressure is 50 psi on a handline and 80 psi on a master stream (both editable). A discharge estimate; incident command and the pump operator govern the actual flow target.
Formula and source
gpm = 29.7 x bore_in^2 x sqrt(nozzle_pressure_psi); companion nozzle reaction = 1.57 x bore_in^2 x nozzle_pressure_psi.
IFSTA Pumping Apparatus Driver/Operator Handbook smooth-bore discharge form (by name); classical orifice discharge, no edition cycle.
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