UV Light Air Purification: Separating Myth From Reality
Indoor air quality has become a topic of increasing concern in recent years. Studies performed by the Environmental Protection Agency have found that the indoor concentration of certain pollutants may be up to five times greater than outdoors. To keep such pollutants from leading to unwelcome health problems, many homeowners have turned to air purification systems.
Some of the most effective air purifiers are those that harness the power of ultraviolet light, or UV light for short. Unfortunately, UV air purifiers have also been the source of much misinformation. This article offers a useful introduction to these powerful appliances.
How HVAC UV Purifiers Work
Some of the most problematic indoor air pollutants are microorganisms like mildew, mold, and bacteria and viruses, which often take up residence inside of a home's HVAC ducts. Ultraviolet air purifiers specialize at neutralizing any unwanted pests present in your air system. Specifically, ultraviolet light passes through the cell walls of microorganisms and disrupts their DNA.
In other words, simply by shining on a microscopic germ, UV light can kill it completely. This prevents those germs from leading to infections, allergies, and other illnesses. The exact same principle used in today's UV air purifiers has been safely used since the mid-20th century for the purposes of medical sanitation and drinking water sterilization.
Three Types of UV Light
Not all ultraviolet light is capable of acting as a germicidal agent. Ultraviolet light comes in three distinct varieties, depending on its wavelength: UV-A, UV-B, and UV-C. Confusion about these three different types lies at the heart of much of the misinformation surrounding UV air purifiers.
UV-A light makes up 95 percent of the sun's radiation that gets to the earth. Excessive exposure to UV-A in natural sunlight leads to skin wrinkles and other signs of premature aging. UV-B also exists in the sunlight that makes it through the atmosphere, and is particularly harmful to humans, as it leads to sunburns, skin cancer, and other serious ailments.
UV-C is the most dangerous form of ultraviolet light. Of the three types, it also has the shortest wavelength — so short that none of the UV-C produced by the sun ever makes it through the earth's atmosphere. Yet when UV-C light is artificially generated, it proves highly effective at destroying microorganisms.
UV purifiers exclusively use UV-C in order to keep the air of your home free from dangerous microorganisms. Because this light is safely hidden inside of your HVAC system and is never released into the rooms of your home, it can do its job without posing any threat to you or your family.
Benefits of UV Air Purifiers
The greatest benefit of a UV air purifier lies in its ability to eliminate potentially harmful microorganisms from your home's air supply. To understand why this makes UV purifiers so unique, you must first understand that most physical filtration systems cannot capture or remove microorganisms from your air.
That's because those microorganisms are many times smaller than the sorts of things air filters are designed to capture — things like dust, smoke, pet hair, and pollen. Most types of germs are small enough that they can pass right through a standard air filter. Certain microorganisms — viruses, for example — are even small enough to pass through HEPA filters.
Homeowners should understand that, despite the powerful abilities of UV air purifiers, they are best implemented along with traditional filtration systems. Likewise, homeowners must be prepared to have the UV bulbs in an air purifier changed every few years since the bulb will gradually lose effectiveness as it ages. To learn more about how to best harness the power of UV purification in your home, contact the HVAC installation and maintenance experts at American Air Cares.