Standpipe Outlet Pressures-Are You in the Ballpark?

When selecting hose and nozzle configurations for standpipe use, its important not to forget hydraulics.  Too often, the biggest issue considered is the weight of the equipment.  This is important, but weight can be managed in  the way that the hose and equipme t is bundled.

The following are required standpipe OUTLET pressures for the listed hose and nozzle configurations.  This is the pressure required at the standpipe outlet, not factoring in any elevation loss or gain going up or down stairs.  Add 5 PSI per floor going up or subtract 5 PSI for each floor going down from the outlet.  The values represent the total pressure required to deliver the listed flow from the given hose and nozzle combination.  No other pressure, aside from elevation or appliance losses/gains need to be added.

The below data represents approximate pressures based on known pressure loss values on commonly available pressure loss charts.  The numbers are rounded slightly in some cases to the nearest 5 PSI value for the sake of simplicity.  Certain brands of fire hose will perform better, such as "Ponn Conquest", where the pressure loss of this particular 1 3/4" hose represents a value closer to 2" hose.  Pressure loss charts for this hose and other brands are found on each manufacturers websites.

1 3/4" Hose 100 PSI Fog Tip 150 GPM
This includes automatic standard pressure, selectable and fixed gallonage nozzles

• 100 FT Hose: 135 PSI
• 150 FT Hose: 150 PSI  *NOT LIKELY*
• 200 FT Hose: 170 PSI  *NOT OBTAINABLE*

1 3/4"Hose 50 PSI Tip 150 GPM
This includes 7/8" Smooth Bore or Low Pressure 50 PSI Fog tips

• 100 FT Hose: 85 PSI
• 150 FT Hose: 100 PSI
• 200 FT Hose: 120 PSI

1 3/4" Hose 100 PSI Fog Tip 180 GPM
This includes automatic standard pressure nozzles and standard fog nozzles with this flow setting

• 100 FT Hose: 145 PSI
• 150 FT Hose: 170 PSI  *NOT OBTAINABLE*
• 200 FT Hose: 190 PSI  *NOT OBTAINABLE*
 

1 3/4" Hose 50 PSI Tip 180 GPM
This includes the 15/16" Smooth Bore tip, which is the most common tip for this flow.

• 100 FT Hose: 95 PSI
• 150 FT Hose: 120 PSI
• 200 FT Hose: 140 PSI
 

2" Hose 100 PSI Fog Tip 180 GPM

• 100 FT Hose: 120 PSI
• 150 FT Hose: 130 PSI
• 200 FT Hose: 140 PSI

2" Hose 50 PSI Tip 180 GPM
This includes the 15/16" smooth Bore tip.

• 100 FT Hose: 70 PSI
• 150 FT Hose: 80 PSI
• 200 FT Hose: 90 PSI
 

2" Hose 50 PSI Tip 200 GPM
This includes the 1" smooth bore tip or low pressure fog tip

• 100 FT Hose: 75 PSI
• 150 FT Hose: 90 PSI
• 200 FT Hose: 100 PSI

2" Hose 50 PSI Tip 250 GPM
This includes the 1 1/8" Smooth Bore tip and low pressure fog tips

• 100 FT Hose: 90 PSI
• 150 FT Hose: 110 PSI
• 200 FT Hose: 130 PSI

2 1/2" Hose 50 PSI Tip 250 GPM
This includes the 1 1/8" Smooth Bore tip and low pressure fog tips

• 100 FT Hose: 70 PSI
• 150 FT Hose: 75 PSI
• 200 FT Hose: 80 PSI