Required Fire Flow

ISO method from square footage and exposure.

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Details, formula, and sources

ISO Needed Fire Flow NFF = (C × O × X × P) where C = 18 × F × sqrt(A), F is construction-class factor, O is occupancy hazard, X is exposure factor, P is communication factor.

ISO Public Protection Classification (PPC) Schedule by name.

ISO PPC documents licensed; the per-class 0.6 / 0.8 / 1.0 / 1.2 / 1.5 F-factor multipliers are reproducible from ISO outreach materials.

Estimate. AHJ and licensed fire protection engineer govern.

Field names used by the API: structure_area_ft2, construction_class, occupancy_factor, exposure_factor, communication_factor, needed_fire_flow_gpm, base_C_gpm, construction_factor

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