The NAFA Guide to Air Filtration (1993) quotes Public Health Service Publication No. 953, "Air Filtration of Microbial Particles" (1963)as follows on the subject of airborne microorganisms:
Although electrostatic precipitators can remove a high percentage of bacteria and dust from the air, they may not be satisfactory as filters where a constant supply of clean air is required. Electrostatic precipitators that receive maximum maintenance have been shown in laboratory tests to remove or destroy approximately 90 percent of the microorganisms in the air. However, tests of some units under normal operating conditions have shown much lower efficiencies. Under optimum physical conditions and with satisfactory maintenance, electrostatic precipitators can be used in place of medium efficiency filters. They should be equipped with high-or ultra-high-efficiency filters downstream if the air is to be supplied to critical areas. Without maximum maintenance, electrostatic precipitators can give a false sense of security.
