Choosing an Air Cleaner: Other Concerns
Excerpted from: "Residential Air Cleaning Devices: A Summary of Available Information", Office of Air and Radiation, U.S. Environmental Protection Agency 400/1-90-002, February 1990
What additional factors should be considered in deciding whether to use an air cleaner? Several factors other than the ability of air-cleaning devices to reduce airborne pollutant concentrations should be considered when making decisions about using air cleaners. These include:
Installation, Use and Need for Maintenance
The air-cleaning unit may have certain installation requirements that must be met, such as an adequate and accessible power supply or the need for access during use, repairs, or maintenance. After installation, operating and maintenance procedures specified by the manufacturer need to be followed to assure adequate performance from the air cleaner. Filters and sorbents must be cleaned or replaced and plates or charged media of electronic air cleaners must be cleaned, sometimes frequently.
Cost
Cost may also be a consideration. Major costs include the initial purchase of the unit, maintenance costs (i.e., cleaning and/or replacement of filters and other parts), and operating costs (e.g., costs for electricity). In general, the most effective units (e.g., those with high air flow rates and efficient particle capture systems) are also the most costly.
Production or Redispersal of Pollutants
Another consideration is whether some units will produce new pollutants or redisperse old ones. The potential for ion generators and electronic air cleaners to produce ozone, a lung irritant, may be of concern, particularly if electronic air cleaners are not properly installed and maintained. This requires further study. At least two manufacturers of portable units advertise that their products produce ozone to facilitate removal of harmful gases, but the levels produced by these devices and the possible health effects are not known.
Inability to Remove Some Odors
A number of air cleaners tested were found to reduce the levels of cigarette smoke particles in the air. However, the odor of cigarette smoke remained because many of the devices do not contain effective systems to remove the gaseous products of cigarette smoke.
Possible Effects of Particle Charging
Another factor with respect to ion generators, particularly those that do not trap some of the charged particles, is the effect of particle charging on deposition in the respiratory tract. Experiments have shown a linear increase in particle deposition with charge; therefore, the use of ion generators may not reduce the dose of particles to the lung.
Noise
Noise may be a problem with air cleaners containing a fan. Some portable units operating at high speed can produce noise equivalent to a small vacuum cleaner or that made by light traffic at 100 ft. Even at low speed, some models produce an annoying hum or whine.
EPA: Indoor Air Pollution: An Introduction for Health Professionals >
|
