Foam Concentrate
Required foam volume by class and application rate.
Example
You enter
- Fire area (ft²) 1500
- Application rate (gpm/ft²) 0.1
- Foam concentrate (percent) 3
- Duration (min) 15
You get
- Solution flow 150 gpm
- Concentrate 4.5 gpm concentrate
- Total concentrate 67.5 gal
- Total solution gallons 2250
Checked against published worked examples from: NFPA.
Details, formula, and sources
Formula or tableFoam concentrate volume = application_rate (gpm/ft²) × area × duration × concentration_pct. Class A typical 0.1-0.5%, Class B AFFF/AR-AFFF 1-6%.
Source and editionNFPA 11 (Standard for Low-, Medium-, and High-Expansion Foam) by name; manufacturer foam-concentrate technical data (National Foam, Chemguard, Solberg) by name.
Free accessNFPA 11 read-only at nfpa.org/freeaccess.
What governsEstimate. AHJ and licensed fire protection engineer govern.
API field namesfire_area_ft2, application_rate_gpm_per_ft2, foam_percentage, duration_min, total_solution_gpm, concentrate_gpm, total_concentrate_gallons, total_solution_gallons
- Application-rate default 0.10 gpm/ft² default (3% concentrate and 15 min are also prefilled); NFPA 11 sets the rate by hazard and foam type, so enter the rate the fuel, the foam, and the SOP call forNFPA 11