Flow rate or liquid volume based sizing for grease interceptors is inaccurate and inadequate, having led to thousands and thousands of incorrect installations across North America.
Grease Production Sizing is the only method that considers how much grease a restaurant will produce to ensure that the grease interceptor selected has enough capacity for a consistent and affordable pumpout schedule.
Here is a link to the video if you want to check it out:
http://youtu.be/c3HLV3dF89c