Electronic air cleaner applications

The NAFA Guide to Air Filtration (1993) identifies factors affecting the use of electronic air filters:

• Ozone: One of the major considerations in electronic air cleaner design is the prevention of ozone formation. An oxygen molecule contains two oxygen atoms. Ozone consists of three oxygen atoms and is a relatively unstable molecule that is a toxic gas. The EPA has set guidelines that establish maximum exposure levels of this gas for human health and safety. Ozone formation is minimized or eliminated by proper ionizer design and by proper maintenance of an electronic air cleaner.
• Capacity: The amount of air handled by an electronic air cleaner relates to the velocity sensitivity of the device. It can be underrated with improved efficiency. Conversely, the efficiency may fall off significantly when the device is overrated.
• Uniform air flow: As mentioned previously, electronic air cleaners are velocity-sensitive. It is important that they be installed in a location and with suitable baffles, if necessary, so that the flow of air to be filtered passes through the entire unit at a uniform velocity.

Different arrangements for cleaning electronic air cleaners ... [have] design considerations [that] must be ...[included] which will make it easy to clean the units whenever this becomes necessary. Time for cleaning may be dictated by amount and type of airborne contaminants accumulating on plates.