Air Purifiers
How many people have air purifiers? Probably more than we think. What exactly are air cleaners ? It's a device used to remove contaminants from the air. Anyone who suffers from allergies or asthma might benefit from one. They are also touted to reduce or eliminate second-hand smoke. They are manufactured as stand-alone units or ones that can be attached to HVAC units usually found in medical and commercial industries.
Allergens, including dust, pollen, pet dander, mold spores and dust mites can trigger allergies in people. Volatile organic compounds, known as VOCs cause people exposed to them to experience symptoms of (sick building syndrome).
Some studies have found that poor air quality is more of a contributing factor in some forms of cancer, respiratory illnesses and other pulmonary infections. So these handy little gadgets might have an impact on many health related issues. They also reduce the need for frequent room and area cleaning. For those of us who hate housecleaning, this would be sufficient reason alone to purchase one. They only use a small amount of electrical energy so they are not very expensive to run and only have minimal environmental effect.
Since there are several different processes that can be used to purify air with varying degrees of effectiveness, it would probably make sense to use more than one process in a purifier. Air purifiers are capable of combining more than one process.
Filter based purification is one process that traps airborne particles by size exclusion. Particles are physically captured by the filter when air is forced through it. HEPA filters are probably the ones we are most familiar with. They must be arranged so that no air bypasses the HEPA filter. If the environment is really dusty, the HEPA filter may follow a conventional filter that will remove coarser impurities so that you won't need to clean or replace the HEPA filter frequently. Another feature of HEPA filters is that they don't generate harmful byproducts.
Activated carbon can absorb volatile chemicals but not large particles. When using activated carbon it may be difficult to completely remove contaminants. It is merely a process of changing contaminants from a gaseous phase to a solid phase. These same contaminants when disturbed can be regenerated in indoor air sources. Even so, it has a long history of commercial use. It can also be combined with HEPA.
Some consumers are concerned with hazardous gaseous by-products, frequency of filter replacement, noise levels and electrical consumption. Some air purifiers in the U.S. are certified as Energy Star and are very energy efficient.