Fire Hose Friction Loss

Formula and source

Friction loss FL = C × Q² × L per 100 ft of hose. C and L per hose diameter from NFA training tables (1.75 in, 2.5 in, 3 in, 4 in, 5 in, etc.).

National Fire Academy hose-hydraulics training materials (U.S. government, public domain).

Audience

This tile is built for fire-ground and the adjacent professions in the Fire-Ground Engineering group. The interactive calculator runs entirely in your browser. No account, no fee, no advertising, no tracking.

Related tools

• Pump Discharge Pressure
• Hydrant Flow
• Required Fire Flow
• Reverse-Lay Friction Loss

Posture

Rough Logic answers the math question the working professional asks on the job. The site is a calm, fast, ad-free, account-free, ever-free reference. It does not interpret code. It does not replace the licensed professional. It does not store your inputs. The Authority Having Jurisdiction governs all installations and inspections.