Dust in Electrical Equipment

Dust in electrical Equipment can affect the operation of the equipment.  Dust can result in tracking which causes current to flow over the insulation eventually leading to failure.  Dust on the surfaces of conductive parts such as breaker poles or relay contacts can affect the conductivity and cause heating and voltage drops

Dust when combined with oil or water in the atmosphere can form acids which can corrode and weaken the insulation. 

A layer of dust on the surface of an equipment can affect the heat transfer and prevent adequate cooling. 

Hence, equipment which are to be installed in dust prone environments should be adequately dust proof.  Panels should have filters which prevent the entry of dust.