Fire Pump Sizing Calculator
Static · formula-only · worked example computed when this page was built · no live data
The Fire Pump Sizing Calculator picks the rated flow and pressure for a fire-protection duty per NFPA 20 pump-selection rules. Example: for a 500 GPM / 100 psi fire-protection demand, with a 10% design margin, Recommended flow = 2840 L/min, Rated pressure = 7.58 bar, Motor = 55.74 kW (per NFPA 20:2022 | NFPA 13:2022 | NFPA 25 | BFP IRR RA 9514).
How it works
Computed from your inputs per NFPA 20:2022 | NFPA 13:2022 | NFPA 25 | BFP IRR RA 9514. Anything the worked example does not state uses this calculator's standard default; the interactive version shows every input and lets you change it.
Worked example (Fire Protection)
Inputs: a 500 GPM / 100 psi fire-protection demand, with a 10% design margin.
| Result | Value |
|---|---|
| Recommended flow | 2840 L/min |
| Rated pressure | 7.58 bar |
| Motor | 55.74 kW |
Computed by WorkHive's calculation engine when this page was built; standard: NFPA 20:2022 | NFPA 13:2022 | NFPA 25 | BFP IRR RA 9514.
How to use this calculator
- Read the worked example. It uses a 500 GPM / 100 psi fire-protection demand, with a 10% design margin and shows every number in the method.
- Follow the formula with your own figures: it returns Recommended flow, Rated pressure, Motor, computed per NFPA 20:2022.
- To compute interactively, open the Fire Pump Sizing Calculator inside WorkHive's free Engineering Design suite (link below). It runs the same method with your inputs.
FAQ
What is a fire pump sizing calculator NFPA 20?
The Fire Pump Sizing Calculator is a free online tool that picks the rated flow and pressure for a fire-protection duty per NFPA 20 pump-selection rules. It shows the formula and a fully worked example so you can check the method, not just the number.
How is it calculated?
The result is computed from your inputs following NFPA 20:2022. The worked example on this page shows a real computation with real numbers.
Is the calculator free?
Yes. WorkHive is free: this worked example is open to everyone, and the interactive calculator runs inside the free Engineering Design suite after a free sign-up (your work is saved to your account). WorkHive is a free, offline-first maintenance platform built for Philippine industrial plants.
Run it on your own numbers
Open the interactive Fire Pump Sizing Calculator in WorkHive. Free, and a free sign-up saves your calculations, BOMs and scope-of-works to your account.