Grease interceptor sizing methodology, where FOG separation is required, hydromechanical (indoor) vs. gravity (outdoor) interceptor types, and maintenance/pumping requirements.
Fats, oils, and grease (FOG) from commercial kitchens congeal in piping in a way ordinary sanitary waste never does, threatening both a building's own drains and the shared municipal sewer main — which is why FOG control runs under its own Clean Water Act-authorized pretreatment programs rather than ordinary sanitary drainage sizing. This module covers where grease interception is actually required, the difference between an indoor hydromechanical grease interceptor (HGI) and an outdoor gravity grease interceptor (GGI), the PDI G101 flow-rate and retention-time sizing methods with worked examples, and the maintenance and pumping intervals that keep a correctly sized interceptor performing as designed.
By the end of this module you should be able to size a standard HGI from fixture volume using the PDI G101 method and explain why floor drains, restroom fixtures, and mop sinks must never be routed through a grease interceptor.