Air Cleaning Devices for Buildings (with Central Air-Conditioning System)
Air cleaning devices can be fitted to regulate particulate levels in buildings with central air conditioning systems during a prolonged smoke haze period. The devices include electrostatic precipitators and media filters.
Electrostatic precipitators operate by electrically charging dust particles as they pass a set of electrodes. The charged particles are subsequently collected by charged collector plates (with an opposite charge) downstream of the charging electrodes. They have minimal effect on airflow.
Media Filters are mats of fine fibres that are oriented perpendicular to the direction of airflow to intercept and trap particulate. They are available in a wide range of capture efficiencies. For smoke haze, filters manufactured for more efficient removal of fine particulate should be used. The conventional medium to high efficiency media filters that can trap fine particulate are typically dense and may hinder air flow if the fans are not designed to match them. There is another type of medium efficiency filter that uses electrostatically charged fibres to attract and retain fine particles. These filters are less dense and therefore exert a lower resistance to air flow.
The capital and operating costs vary depending on the particular type of air cleaning devices selected and the design of the air-conditioning system. Based on NEA's assessment, the overall annual cost ranges from $2,000 to $10,000 for a floor area of 1,300 sqm. The costs are for an assumed haze period of three months per year. The system suppliers will be able to provide buyers with the actual costs of each option.
For more information, please view the List of Suppliers of Air Cleaning Devices for Buildings.
Information from US-EPA webpage on Residential Air Cleaning Devices
Information from American Lung Association webpage on Indoor Air Quality