Effectiveness of indoor air cleaning with corona ionizers

The paper presents an experimental evaluation of the effectiveness of indoor air cleaning from dust particles from the 0.3 to 2.5 μm size range with corona ionizers. Dust particle concentration was measured in a 50-m3 unoccupied office room. Local ionization (portable ionizer: 3 electrodes, −6 kV) of the air inhaled by the phantom and whole room air ionization (net of electrodes hung beneath the ceiling) were tested. Particle concentration was measured with a laser counter Microair 5230 (HIAC-ROYCO). After 2 h of whole room ionization (“ion shower”) particle concentration was reduced by up to two orders of magnitude. Local ionization reduced the dust concentration in inhaled air by several percent.