L. E. Sparks I.S. Environmental Protection Agency Air and Energy Engineering Research Laboratory MD 54 Research Triangle Park, NC 27711

Ozone emissions were measured from a short wireplate precipitator and three commercial electronic air cleaners. Ozone generation was most strongly affected by the mrona current and polarity of the discharge electrode. To a lesser extent, the type of corona (i.e., whether tuft or glow) was also important. Water vapor seems to reduce the ozone emission rate for negative corona, but ozone emissions from positive coronas are relatively unaffected. Ozone emission rate was also affected by the radius of the discharge electrode, but the measured values did not fit Castle’s model.