Standpipe Pump Discharge Pressure (NFPA 14)
Standpipe pump discharge pressure: nozzle, hose friction, appliance loss, and elevation.
Example
You enter
- Standpipe class I
- Highest outlet above pumper (ft) 110
- Required nozzle pressure (psi; blank = 100 Class I/III, 65 Class II) 100
- Design flow (GPM) 250
- Appliance loss (psi) 25
- Supply hose length (ft) 200
- Supply hose diameter 3_in
- Building height (ft) 120
You get
- Pump discharge pressure (psi) 181
- Elevation loss (psi) 47.74
- Supply friction (psi) 8.46
Checked against published worked examples from: NFPA 14 / National Fire Academy.
Details, formula, and sources
ScopeRequired pump discharge pressure = nozzle pressure + supply-hose friction (NFA CQ^2L) + appliance loss + elevation (0.434 psi/ft), with a high-rise flag. SOP and incident command govern.
Formula or tablePDP = nozzle pressure + supply-hose friction (NFA CQ²L) + appliance loss + elevation (0.434 psi/ft × highest outlet above pumper). Negative elevation (below the pumper) subtracts.
Source and editionNFPA 14 (2024) §7 (Standpipe System Design) by name and section; National Fire Academy CQ²L hydraulics.
Free accessNFPA 14 read-only at nfpa.org/freeaccess; NFA materials free at usfa.fema.gov.
What governsEstimate. AHJ and licensed fire protection engineer govern.
API field namesstandpipe_class, highest_outlet_elevation_ft, nozzle_pressure_psi, design_gpm, appliance_loss_psi, supply_hose_length_ft, supply_hose_diameter, building_height_ft, pdp_psi, elevation_loss_psi, supply_friction_psi
- Appliance loss 25 psi default for the standpipe system (intake, riser check, hose valve, FDC); user-adjustableNFPA 14 / IFSTA typical
- Design flow 250 GPM default (Class I/III; 100 GPM for Class II) at the topmost outlet; the system demand (500 GPM first riser) governs the supplyNFPA 14-2024 §7