Fire Suppression
Hydraulic Estimator
Friction loss across one pipe segment. Hazen-Williams × length. Useful for spot-checking; full hydraulic design needs HASS / AutoSPRINK.
⚠ Single-segment estimator only
Sprinkler systems split flow at every tee. Real hydraulic calc iterates K-factor balancing at each node. Use this to estimate one pipe run, not size a whole system.
FAQ
Equivalent length for fittings? +
A 90° elbow on 2" pipe ≈ 5 ft equivalent. A tee through-flow ≈ 3 ft. A tee branch ≈ 10 ft. Add these up and add to actual pipe length. NFPA 13 Table 23.4.3.1.1 has the full list.
Why does NFPA require C=100 for steel? +
It accounts for scale/buildup over the life of the system. New steel might be 130 but you can't design at that.
Max velocity? +
No hard NFPA cap, but velocities over 25 ft/s create water hammer and noise. Practical limit is around 20 ft/s.