Waste waters that drain from kitchens and other food preparation facilities are directed into the grease traps where the water current subsides. Silt is deposited on the bottom of the first compartment while grease builds up on the surface of the second compartment. The size of the grease trap is determined with respect to the highest possible discharge of contaminated water, the type of contaminant, temperature, the use of washing detergents and other criteria as specified in the EN 1825-2 and DIN 4040-2 standards.
Grease traps are dug in or free-standing containers. Dug in grease traps may be installed in trafficked or non-trafficked surfaces. Lids must be accessible for emptying.