Standpipe TestingDownload PDF
A standpipe is the vertical piping that connects fire sprinkler systems and hose stations between multiple floors. It is common to see standpipes in stairwells of high-rise buildings. A rooftop standpipe test verifies the water supply, pump and piping at the topmost part of the system.
In the past, the only way to perform rooftop standpipe tests was with playpipes and hand-held pitots. Safely securing playpipes and controlling discharge water to avoid interfering with pedestrian and vehicle traffic was a significant challenge, typically requiring that testing be in the early morning hours. The introduction of the Hose Monster® line of equipment changed all that. The Hose Monster neutralizes the dangerous thrust and controls discharge water on the rooftop while minimizing hazards to pedestrians and property below. Flow-rate is measured with FM Approved accuracy.
In some cases, discharging the water can be a challenge since you may be in a stairwell or basement. The In-Line Pitotless NozzleTM can take flow-rate measurements at the valve, allowing you to run hose or piping to a drain or down several flights of stairs.
How often should I test rooftop standpipes?
Every five years. According to NFPA 25, 188.8.131.52, 2010, “A flow test shall be conducted every five years at the hydraulically most remote hose connections of each zone of an automatic standpipe system to verify the water supply still provides the design pressure at the required flows.”
Where do I find more information on this testing?
- NFPA 25, Chapter 6 — Inspection, testing and maintenance of standpipe and hose systems
- NFPA 14 — Installation of standpipes and hose systems
What equipment do I need?
A standpipe test requires a minimum flow-rate of 500 GPM for the most hydraulically remote standpipe and 250 GPM for each additional. This means that the user will have to measure 500 GPM for certain and 250 GPM if there are additional standpipes that need to be flow tested.
1. Little Hose Monster™ (HML) — Use one unit per flowing hose line to diffuse the water at the end of the hose.
2. Pitotless Nozzle™ (PN1.75GRV, PN1.125GRV) — Use a 1 3⁄4" Pitotless Nozzle to read the first 500 GPM. If reading 250 GPM, a 1 1⁄8" Pitotless Nozzle is needed.
3. In-Line Pitotless Nozzle (INPN1.125, INPN1.75, INPN2) — Allows you to take the flow readings directly at the discharge valve with hose or piping attached downstream. Can be used in place of the Pitotless Nozzle and Little Hose Monster to measure flow, however, a Little Hose Monster may still be used to diffuse the water at the end of the hose.
4. Test Hose (2 1/2" Hose) — The length of hose depends on the layout of the job. We offer 21⁄2" x 10', 25' and 50' long. Shorter is usually better, easier to handle and has less friction loss. Use one hose per nozzle.
5. Discharge Flow-Rate Gauge (Gauges) — 60- or 100-psi gauges with a 4" dial are common.
6. Remote Reader (Remote Readers) — Enables you to take gauge readings at a convenient distance from discharge. Sold in 12', 40' or 60' lengths.
7. Case (Cases) — Store and protect pressure gauges and Pitotless Nozzles.
8. Stream Shaper (SS1) — Use to prevent hose burn.
9. 45° or 30° Test Header Elbow (Elbows) — Re-angles the hose from the test header to minimize kinks and hose burn.
10. Spanner Wrench (WSPA101, WSPA104) — For attaching the hose to the test header or to a 21⁄2" Hose Monster.
11. Gauge Calibration (Gauge Calibration) — We offer gauge- calibration service, including a NIST certificate for new and used gauges. NFPA recommends test gauges be calibrated within 12 months prior to the test.
12. Clamp-on Ammeter — Measures pump amperes.
13. Tachometer — Measures pump RPM.
14. Pump Discharge Gauge (Gauges) — A 200- or 300-psi pressure gauge with a 4" dial is common. The dial should be at least 200 psi and be capable of indicating pressure to at least twice the rated working pressure of the pump (NFPA 20, 184.108.40.206).
15. Pump Suction Gauge (Compound Gauge) — If the minimum pump suction pressure is below 20 psi at any flow condition, the suction gauge shall be a compound pressure and vacuum gauge. A compound gauge that reads from 30 Hg to 160 psi or 200 psi with a 4" dial is common (NFPA 20, 4.10.1).