Electrically Charged Dust in Rooms

Inefficient electrostatic air cleaners may allow the escape of dust particles carrying electric charges of one sign. Such charged particles, suspended in the air of a room, create a space-charge potential. The resulting voltage gradient drives the charged particles toward the walls. Because of this space-charge effect, the full benefit of air cleaning may not be realized. In addition to the efficiency of the electrostatic air cleaner, other important factors are the concentration of particulate matter in the air, and room size and shape. Ordinarily, the space-charge problem can be solved by high-efficiency cleaning, under particularly severe conditions, such as especially dirty locations and large rooms (such as auditoriums), the use of a neutralizing device may be desirable.