FOGS Defined


The term FOG  is short for  (Animal, Vegetable) Fats, Oil, Grease  which are generated by food preparation activities.

  • They show themselves in the  the drain lines of cooking equipment and washing equipment where they are part of the effluent flow to the public sewer, and are mixed in with water, solids and detergents.  
  • If these FOG’s enter the sewer system they are major contributors to internal build up on the pipe walls and so reduce the effective capacity of the sewer line to carry the effluent to the sewage processing works. In extreme cases a flu blockage of the sewer line occurs and the effluent then backs up towards the nearest and lowest point of relief. This may be the floor drain of the offending restaurant kitchen  or it may be in an adjacent building or rental unit. In any event the resulting mess causes a shut down of the businesses  involved until the problem can be rectified.
  • The end result is either direct loss of income along with expense to repair or replace damaged finishes and fixtures.
  • Direct costs of  damage and loss of profit can be expected by the offending restaurant along with further financial recompense to any other affected business or properties. 

Fats, oil and grease are present in wastewater in 4 basic forms…

  • Free oil
  • Mechanically emulsified oil
  • Chemically emulsified oil
  • Dissolved oil

Solids in wastewater are present in 2 basic forms

  • Solid particles
  • Soluble particles

Where do FOGS come from? The sources are wide ranging…

  • They are naturally present in a number of goods
  • They are a natural consequence of cooking
  • They are used as cooking mediums and incorporated into ingredients