How Do I Size These Grease Interceptors?

Currently, the most common sizing method is still the Restaurant Sizing Formula found in the Florida Plumbing Code (section 1003.5.1), This method gives you a sizing requirement in gallons. Once you have the "Gallons" required, you can find the properly sized Schier unit using the link below.

In addition to the restaurant sizing formula, interceptors can also be sized by flow rates and storage capacity.

To properly size a ASME or PDI approved grease interceptor you would total the cumulative drainage capacity of the three compartment sink, all floor sinks, dishwashers, and other devices that discharge into the grease line. This would give you the total maximum potential flow rate. Using this maximum potential flow rate, you will have the necessary flow capacity of the grease interceptor.

You cannot size an interceptor solely based on flow rates. You must also take into account the grease retention capacity. The grease interceptor must have sufficient grease storage capacity to hold all of the incoming grease accumulated between pump outs.




CLICK HERE - For the Gallons to G.P.M. crossover chart

CLICK HERE - For the Restaurant Sizing Formula

CLICK HERE - For PDI's Guide to Sizing Grease Interceptors

CLICK HERE - For the WERF Table showing actual peak flow rates of established restaurants

CLICK HERE - For the ASPE (American Society of Professional Engineers) Pipe Size Formula

CLICK HERE - to return to Grease Reference Main Page