| Many people mistakenly assume that an air | | | | namely electrostatic precipitators and charged |
| conditioning only controls the temperature of a | | | | media filters. In electrostatic precipitators, particles |
| living space. Air conditioning also involves the | | | | are collected on a series of charged plates, |
| cleanliness of the air. Filtration is an excellent way | | | | whereas in charged media filter devices, the |
| to accomplish air cleaning and provide enhanced | | | | particles are collected on the charged fibers of |
| levels of comfort to a building's occupants. | | | | the filter. The most efficient filters are |
| Continuous exposure to unfiltered air results in | | | | electrostatic precipitator, because in most of the |
| asthma, allergies, and breathing problems. | | | | electrostatic precipitators, the particles are |
| Generally, air-conditioning systems include | | | | deliberately ionized (charged) before the collection |
| electronic air filters, which use electrical charges to | | | | process, resulting in higher collection efficiency. |
| attract and deposit 95% of household allergens | | | | These precipitators generate approximately |
| and irritants to the human body. An electronic air | | | | 20,000 volts to give dust particles a static electric |
| cleaner is installed between the furnace and the | | | | charge. |
| air ducts to improve indoor air filtration throughout | | | | In order to determine the efficiency of an |
| the home. | | | | electronic air filter, there are two tests: the |
| The air inside the home circulates through the | | | | weight-arrestance test and the atmospheric |
| cooling system, carrying millions of airborne | | | | dust-spot test. In the weight-arrestance test, the |
| particles with it. When this air is drawn into the | | | | efficiency is tested on the basis of the weight of |
| system or device, a pre-filter in the electronic | | | | the dirt removed by the filter. However, this |
| filter traps the majority of the allergens and | | | | method will not give any idea as to the removal |
| irritants. Those particles that do pass through the | | | | of smaller dirt particulate, which can be easily |
| pre-filter receive an electric charge inside the filter. | | | | inhaled by lungs. The atmospheric dust-spot test |
| Collector plates of the filter attract these particles | | | | determines a filter's ability to capture particles |
| and hold them until the cells are cleaned. Electronic | | | | between 0.3 and 6 microns. Whatever test is |
| air cleaners offer the optimum balance between | | | | used and whatever may be the type used, the |
| air filtration and system pressure drop (air | | | | electronic filter must be cleaned at least once in a |
| restriction). | | | | month to improve the indoor air quality. |
| There are two main types of electronic filters, | | | | |