Air Purifiers

Benefits:

Research has demonstrated that air purifiers can alleviate respiratory symptoms due to allergies or asthma as well as eye, nose, and throat irritations. Air filters and air purifiers can be particularly useful in lowering the exposure to airborne pet dander. Air purifiers can also significantly reduce household odors caused by cigarette smoke, kitchen odors, and other sources of unwelcome odors. Air purifiers along with vacuum cleaning are the two most effective tools for clean indoor air.

The use of air purifiers in the Household

Due to increases in air pollution, changes in building construction methods, and decreases in overall physical health of Americans. There has been a dramatic increase in the number of people suffering from asthma and allergies. This dramatic and alarming increase in respiratory sufferers has been intensely researched. In the United States the number of asthma sufferers alone has doubled since 1980. It is difficult to know exactly what will be the trigger substance or allergen for any particular person. The most significant means of controlling the adverse reactions of respiratory sufferers is to combat the allergens on the home front, that is, improving indoor air quality. It has been shown that air purifiers can have a positive effect on respiratory sufferers and three out of every ten households now have a portable air cleaner. A recent study from the New England Journal of Medicine concluded that respiratory relief could be achieved by adopting a set of preventive measures including the use of air purifiers and that there can be an improvement in asthma-related symptoms with an air filtration system.

The fact is, unfortunately, there are a wide variety of airborne pollutants that can be commonly encountered in a residential dwelling. There are basically two types of airborne pollutants: microbiological agents and chemical agents.

Microbiological agents include pollens, bacteria, fungi, fungal spores, viruses, and dust mites (microscopic arachnids that live in bedding) and cockroach debris, allergens, pet dander (from dogs and cats), mold and mildew, and non-biological particles such as dust, tobacco smoke, and cooking-generated particles.
Chemical agents including common household cleaners, paints and paint stripper, and pest control products.

Types of purifiers:

There are several basic types of purifiers:

Mechanical (HEPA filtration, etc),
Electronic (electrostatic precipitator, ion-charging devices (ICD) also called ionic air purifiers.)
UV or ultraviolet hybrid.
Any combination of the above three types.

Mechanical devices force air through a filter, most often a HEPA (high-efficiency particulate air) filter, which traps particles such as pet dander, smoke, pollen, dust, dust mites, and molds that are 0.3 microns or larger
The electronic air purifiers work by different methods but on the same principle. They negatively or positively charge ions, which then either attracts like a magnet to an oppositely charged plate or they are sent back into the room where they attract each other.

Things to consider:

Filter efficiency: You want a filter that can remove the smallest particles (some go down to .1 micron) with the highest percentage of particles (pollutants) captured. The particle removal efficiency is an important consideration. This information can also be found at www.cadr.org.

Operator involvement: How much work is involved in the operation of the air-purifying unit? Filters need to be replaced, plates need to be cleaned, etc. It is important to carefully think about whether or not you will be faithful in maintaining the equipment to insure that it is working at its peak efficiency for you. There are various types of purifying units that require virtually no user intervention to units, which require more routine maintenance. The tradeoffs between unit performance and user maintenance needs to be carefully weighed.

Costs: filter costs are important to consider as well as the electrical costs to running a device either continuously or intermittently. These costs can mounts especially if there will be multiple units being used. These costs can be calculated.

Manufacturer claims: Like label reading in the grocery store, air purifiers and filters should come with their set of labels detailing information about their capabilities and this information has been independently verified. What should the labels say? There are several independent organizations that test air purifiers: Association of Home Appliance Manufacturers (AHAM) www.aham.org. For the efficiency of a unit to remove cigarette smoke, consult the information on the clean air delivery rate at www.cadr.org: the higher the number, the greater the efficiency.

Warranties: Not only are there the claims made for a particular air purifier model, what are their warranties.

Room placement:: It must be remembered that the way in which the purifier is effective is through the circulation of air through the purifier. It is necessary to make sure the portable purifier is placed in such a manner as to allow for the maximum movement of the air in the room through the purifier. The EPA recommends the following:

Place portable air cleaners so:

They are near a specific pollutant source, if one exists.
They force the cleaned air into occupied areas.
The inlet and outlet are not blocked by walls, furniture, or other obstructions.
For in-duct devices, assure that the inlets and outlets of the heating or cooling system are not blocked by furniture and other obstructions.