To effectively remove FOG, a gravity grease interceptor must retain the water long enough for the FOG and settleable solids to separate within the baffle chamber. Lake County Special Districts suggest that gravity grease interceptors are sized to match the number of Drainage Fixture Units (DFUs) of the kitchen or source as follows:
Gravity Grease Interceptors Sizing Table
|Drainage Fixture Units (DFUs)||Gravity Grease Interceptors Volume (Gallons)|
Example #1: Typical fast food kitchen = 17 DFUs = 750 gallon GGI
Example #2: Typical larger kitchen = 45 DFUs = 1250 gallon GGI
Please note: For a smaller hydro-mechanical unit, use the Hydro-Mechanical Grease Traps Calculation Sheet (PDF).