NFPA 25 worksheet
Hydrant Flow and Water Supply Worksheet
A water supply worksheet for hydrant pitot flow, static and residual pressure, available flow at required residual, and sprinkler demand comparison.
hydrant flow water supply worksheet3 workflow phases6 linked tools4 required inputs
Workflow phases
3
Ordered job steps
Linked calculators
6
Tools used by the worksheet
QA gates
3
Review checkpoints
Page role
Use this page for a defined task before moving to the next project record.
- Audience
- Fire protection engineers, ITM contractors, Water supply reviewers, AHJ reviewers
- Job
- Static pressure, residual pressure, test flow, pitot pressure, and outlet information are available.
- Evidence
- Field test basis: Static pressure, Residual pressure; Comparison basis: Required residual pressure, Test date and location
- Output
- Hydrant flow test calculation; Available flow at required residual; Water supply curve point
- Next
- Run workflow phases in order, pass QA gates, then open related authority records before project reliance.
Worksheet record summary
Input status, phase records, QA review, and filing notes for the project record.
| Record area | Count | Engineering use |
|---|---|---|
| Inputs | 4 required / 2 conditional | Trace each value to an accepted source before tool use. |
| Workflow phases | 3 | Run phases in order and preserve each record. |
| Linked calculators | 6 | Open linked calculators from the worksheet phase where they belong. |
| QA gates | 3 | Retain review evidence before saving the worksheet record. |
Filing notes
- 14 required inputs and 2 conditional inputs recorded with source basis.
- 23 workflow phases connected to 6 calculator handoffs and 1 reference handoffs.
- 33 QA gates retained before final engineering or AHJ review.
- 44 project records retained for the calculation package.
Worksheet fit check
Confirm the worksheet matches the project record before opening every phase.
| Decision | Use boundary | Record to keep |
|---|---|---|
| Use when | A hydrant flow test must become available flow, supply curve, and demand comparison evidence. | Static pressure, residual pressure, test flow, pitot/outlet data, required residual, and test location. |
| Do not use when | The user only needs to convert one pitot reading from a known outlet into an estimated flow. | Use the pitot or hydrant flow calculator and preserve the same-test outlet basis. |
| Retain record | Keep the worksheet when water supply output will be compared with sprinkler demand or used for pump screening. | Available flow at required residual, supply curve points, and demand comparison notes. |
Worksheet input matrix
Trace each required value to its source before running linked calculators.
| Group | Field | Source | Required | Used for |
|---|---|---|---|---|
| Field test basis | Static pressure | Hydrant flow test record | Required | Supply curve and available flow |
| Field test basis | Residual pressure | Hydrant flow test record | Required | Supply curve and available flow |
| Field test basis | Pitot pressure | Field pitot reading | Conditional | Hydrant discharge flow |
| Comparison basis | Required residual pressure | Project demand or AHJ basis | Required | Available flow at residual |
| Comparison basis | System demand | NFPA 13 hydraulic worksheet or system demand calculator | Conditional | Demand comparison |
| Comparison basis | Test date and location | Field report | Required | Record traceability |
Worksheet workflow
Run phases in order so the worksheet answers the full job intent, not only one formula.
| Phase | Objective | Actions | Linked tools | Acceptance gate |
|---|---|---|---|---|
| 1. Record hydrant test | Capture field readings and confirm the test basis before calculations. | Record static pressure, Record residual pressure, Record pitot and outlet data | Field readings belong to the same test event and outlet condition. | |
| 2. Calculate available water | Estimate available flow at the required residual pressure. | Enter measured flow, Enter static and residual pressures, Set required residual, Review available flow | Available flow is reported at the same residual pressure basis used for demand comparison. | |
| 3. Prepare demand comparison | Hand water supply data to sprinkler demand or pump selection workflows. | Compare available flow to sprinkler demand, Flag narrow supply margin, Send result to pump sizing if needed | Supply point and demand point are both retained with GPM and pressure basis. |
Worksheet QA gates
Use these gates before the worksheet result is used for design coordination or review.
| Gate | Check | Evidence |
|---|---|---|
| Test consistency | Static, residual, and flow values are from one test record. | Field test basis input group |
| Residual basis | Available flow is calculated at the required residual pressure. | Available water output |
| Demand comparison | Demand and supply are compared using compatible pressure and flow assumptions. | Demand comparison phase |
Worksheet related tools
Checks that calculators, references, and standards are connected to the worksheet phases where they are used.
| Related item | Kind | Worksheet phase | Listed in worksheet | Back link |
|---|---|---|---|---|
| Fire Pump Sizing Calculator Fire Pump Rated Flow and Pressure Calculator | calculator | 3. Prepare demand comparison | Declared | Linked back |
| Sprinkler System Demand Calculator Sprinkler System Demand Calculator | calculator | 3. Prepare demand comparison | Declared | Linked back |
| Available Water Supply Calculator Available Water Supply Calculator | calculator | 2. Calculate available water | Declared | Linked back |
| Hydrant Flow Test Calculator Hydrant Flow Test Calculator | calculator | 1. Record hydrant test | Declared | Linked back |
| Pitot Flow Calculator Pitot Flow Calculator | calculator | 1. Record hydrant test | Declared | Linked back |
| Water Supply Curve Plotter Water Supply Curve Plotter | calculator | 2. Calculate available water | Declared | Linked back |
| NFPA 13 Sprinkler System Calculators NFPA 13 Sprinkler System Calculators | hub | Worksheet standard context | Declared | Linked back |
| NFPA 25 Flow Test and Water Supply Calculators NFPA 25 Flow Test and Water Supply Calculators | hub | Worksheet standard context | Declared | Linked back |
| Sprinkler Pipe Internal Diameter Reference Sprinkler Pipe Internal Diameter Reference | reference | 1. Record hydrant test | Declared | Linked back |
Records to keep
1Hydrant flow test calculation
2Available flow at required residual
3Water supply curve point
4Demand comparison record
Related calculators and references
Authority records
Document jurisdiction, AHJ, submittal, inspection, or edition-basis records before final project reliance.
Engineering disclaimer
NFPA in USA provides engineering workpapers, calculation checks, and reference tables for project screening and coordination. Final design decisions, code interpretations, submittals, and acceptance records must be completed by qualified professionals and verified against the adopted code, project criteria, listings, and Authority Having Jurisdiction requirements. This site does not issue signed or sealed engineering documents.FAQ
What is the hydrant flow and water supply worksheet for?+
It organizes a complete preliminary engineering check across inputs, linked calculators, reference tables, QA gates, and retained deliverables.
Can this worksheet replace a sealed calculation package?+
No. It is a structured screening and coordination worksheet. Final design, code interpretation, and submittal documents must be reviewed by qualified professionals and the AHJ.
Why use a worksheet instead of a single calculator?+
A single calculator answers one formula. A worksheet follows the job workflow, keeps input sources visible, links the required tools, and records the review gates before project use.