Evolution 9 — Standpipe System Supply

Overview

Standpipe operations require the pump operator to supply water through a building's internal piping system via the Fire Department Connection (FDC). The operator must account for standpipe system friction loss and elevation head for upper floors. Getting the pressure right is critical — too low and the crews on upper floors have no water for their attack; too high and you risk damaging the building's piping system or blowing out hose connections at the standpipe outlet. Most departments use a standard starting pressure for standpipe operations (typically 150 PSI at the FDC) and adjust based on radio feedback from the interior crews. The pump operator cannot see the conditions on the fire floor — they rely entirely on communication and their understanding of the hydraulics involved.

Training Objective

Supply a building standpipe system through the FDC at the correct pressure, accounting for standpipe friction loss and elevation to the operating floor. Maintain stable pressure as interior crews open and close lines at standpipe outlets on different floors.

Skills Practiced

• FDC connection procedures and dual-line supply
• Standpipe pressure requirements by building type
• Elevation head calculation for high-rise (0.434 PSI per foot)
• System friction loss awareness for aged standpipe piping
• Pressure regulation for fixed systems without over-pressurisation
• Adjusting pressure based on radio feedback from interior crews
• Understanding Class I, II, and III standpipe differences

Setup

Hydrant supply to the pump, with two discharge lines connected to the building's Siamese FDC. The standpipe system adds its own friction loss (typically 15-25 PSI for a 5-story building) and elevation demands (approximately 22 PSI for 5 floors) on top of the hose lay calculations from the pump to the FDC.

Scenario

A high-rise fire on the fifth floor of a commercial office building. Interior crews are connecting to standpipe outlets on the fourth floor (one floor below the fire) and need water at the correct pressure. The pump operator supplies the FDC from the street. The building has a Class I standpipe system with 2½" outlets. Crews are using 1¾" attack lines with combination nozzles off the standpipe outlets.

What to Expect

The required pump pressure is higher than typical handline operations due to standpipe friction and elevation. Expect to pump at 150-175 PSI at the FDC. The simulation monitors pressure at the FDC and calculates whether adequate pressure reaches the operating floor. When interior crews open additional lines, pressure at the FDC will drop and the operator must compensate.

Tips

• Standpipe operations typically require 150 PSI at the FDC as a starting point
• Account for both the hose lay to the FDC and the building's internal system losses
• Elevation adds approximately 5 PSI per floor above the pump — a 5th floor fire needs 25 PSI of elevation head
• Coordinate with interior crews about which floor they are operating on — floor changes affect your pressure
• Old standpipe systems have higher friction loss than new ones — when in doubt, pump higher and let the crew adjust at the outlet
• Two lines to the FDC should be balanced — uneven flow causes turbulence in the standpipe riser