UV Air Purifiers: Not All They’re Cracked Up To Be
Air purifiers that provide clean, breathable air is a hot topic nowadays. Retailers and marketers are definitely aware of this fact, and many of them are trying to cash in on the health craze that's been prompted by the revelation that polluted air can have serious repercussions for one's health and well-being. While there are many great products on the market today that clean the air and improve indoor air quality remarkably well, there are just as many that fall far short of their promise. UV - or ultraviolet - air purifiers are one prime example of a product that fails to achieve what it sets out to do - and that might even make the air in your home more hazardous. Also as you read about UV air cleaners the phrase "air sterilization" at times will be used. Keep in mind that sterilization is defined as the complete destruction of all microbial species. Disinfection, meaning reduction of microbial populations, is the correct term for air stream and air cleaning applications.
What Is Ultraviolet Light?
The energy produced by the sun is electromagnetic radiation with many different wavelengths. Only a small portion of these wavelengths are visible to the human eye. These visible wavelengths are seen as colors of the rainbow depending on the wavelength. Waves longer than those seen as red are called infrared. Waves shorter than violet are called ultraviolet. However since ultraviolet is not visible, it is technically not light. Ultraviolet light comes in different lengths too. The range of ultraviolet wavelengths is often subdivided into three groups:
UV-A (380–315 nanometers), is called Long Wave or "blacklight"
UV-B (315–280 nm), Medium Wave,
UV-C (< 280 nm), Short Wave or "germicidal".
UVA and UVB rays that can reach the earth’s surface are primarily non-ionizing and do not have enough energy to ionize atoms. However the longer wave UVA and UVB can cause molecules to vibrate and rotate resulting in heating up.
UV-C is part of the ultraviolet light spectrum that is filtered out by the earth’s atmosphere. The “C” stands for the particular frequency of UV light that kills germs. The shorter wave UVC (used in UV sterilization) light will ionize many atoms and molecules.
According to the University of Pennsylvania Environmental Health and Safety department, UV air purifiers fall short of actually providing health benefits for the people who use them. UV air purifiers use ultraviolet rays of light to neutralize biological contaminants. There is no question whatsoever that ultraviolet light can, indeed, destroy many offensive microbes. UV light can destroy things like dust mites, mold spores and other types of bacteria. Therefore, UV air purifiers are marketed and advertised as doing exactly that; when people use these machines, they think the air in their home is getting cleaner - but it's not.
The Problem with UV Air Purifiers
There's no question that ultraviolet light can neutralize and destroy many types of bacteria and other contaminants - as long as it's given an ample amount of time to do so. The problem with UV air purifiers, though, is that they run the air through far too quickly and the UV light doesn't get enough time to really perform its task. The air gets circulated in, is briefly zapped, and is circulated back out again - usually with the same levels of contaminants as it had in the first place. If you use a UV air purifier, you're not really making a dramatic impact on the indoor air quality of your home.
As if their ineffectiveness wasn't concerning enough, certain studies have shown that UV air purifiers may actually make the air in your home less healthy than it was in the first place. How? By introducing harmful ozone to it. Indeed, it appears that ozone is often a byproduct of the process behind which UV air purifiers work. Considering that, then, it seems that while a small percentage of bacteria is eliminated, it's being replaced with ozone which can seriously jeopardize your health.
HEPA Air Purifiers: A Smart Alternative to UV Air Purifiers
The report issued by the University of Pennsylvania clearly notes that unless a UV air purifier includes a filter and a fan, it is basically useless. This same report states that by a wide margin, HEPA air purifiers are the most effective way to make the air in your home clean. HEPA filters are the gold standard of air purification systems today, and HEPA air purifiers are head and shoulders above UV air purifiers. HEPA technology genuinely removes up to 99.97% of airborne contaminants, making the air in your home wonderfully safe and much healthier to boot. Unlike UV air purifiers, HEPA air purifiers do not produce any harmful byproducts like ozone. The whole purpose of buying an air purifier is to make the air in your home safe and clean, so it makes sense to use a product that will actually do that.
- Administration Staff