ACO Passavant

Sizing calculation methods

Australian water authorities recommend guidelines based on the total volume of liquid to be held in retention and grease separators are sized accordingly.

EN 1825 uses three methods to calculate the required size for a grease separator. The following methods calculate the Nominal Size (NS). The NS (e.g. NS 7) is an approximate maximum flow rate in litres per second permitted to enter the grease separator (i.e. 7L/s).

  1. Number of meals per day
    This method uses the number of meals made in a day to calculate the volume of wastewater to be treated.
  2. Hydraulic load
    This method is based on the maximum flow rate discharged from the kitchen equipment, e.g. dishwashers, tilting kettles and vegetable wash units.
  3. Meat processing units
    This method is based on the number of animals processed per week.

Below is a sizing calculator for grease traps according to EN 1825.