Improving indoor air quality with air purifiers is very straightforward. UV air purifiers utilize UV light technology like far-uv, far-uvc, and UVGI, claiming to kill 99.9% of viruses.
However, do they really work as advertised? In my experience, UV purifiers don’t always live up to the hype.
My experience and growing evidence suggest that UV air purifiers may not be as reliable as they claim to be.
Below, we’ll examine the technology behind UV air purifiers and their effectiveness, so you can decide whether a UV air purifier is the right choice for your home.
How Do UV Air Purifiers Work Exactly?
Traditional air purifiers pull air into the system, pass it through a filter, and release it back into the home. Newer purifiers with UV technology claim to take things to the next level.
A UV light air purifier, sometimes called ‘UV-C sanitizers’ or ‘UV light germ killers’, uses UV light to kill viruses and disinfect or ‘sanitize’ the air. While marketers use fancy terms to describe the technology, the basic principle is quite simple.
UV air purifiers have gained popularity due to their claims of eliminating 99.9% of harmful viruses and bacteria. However, there are questions about the reliability of these devices, with growing evidence suggesting that they may not be as effective as advertised.
Do UV Air Purifiers Really Work Well?
UV air purifiers are becoming increasingly popular, but it’s essential to consider their effectiveness and potential drawbacks before investing in one. While UV light can inactivate infectious bio-contaminants like bacteria and viruses to a certain degree, the specific mechanisms of UV air cleaners aren’t as effective as they might sound.
Bacteria and viruses require extended periods of UV light exposure to be disinfected, often up to several hours. Air often flows through UV air purifiers too fast for the UV rays to make any difference.
Also, UV light does nothing for particles. It doesn’t destroy particulate matter like PM2.5 and ultrafine particles (UFPs), meaning that most dangerous pollutants will still enter your air.
Additionally, many UV air purifiers are also ozone generators. Just like ozone in the earth’s atmosphere reacts with UV rays from the sun, the light and heat in some UV air purifiers can generate heat that turns free-floating molecules of oxygen (O and O2) and water (H2O) into dangerous ground-level ozone (O3).
This type of ozone can be highly toxic. Even short-term exposure can cause a cascade of respiratory symptoms. Long-term exposure has been linked to numerous deadly health conditions.
Finally, it’s worth noting that UV light can burn your skin and damage your eyes. Even brief UV exposure can cause permanent skin and eye damage and even cancer. So always use extreme caution when operating a UV light air purifier and follow the manufacturer’s instructions.
What Does UV Light Do?
UV air purifiers claim to use ultraviolet (UV) light to disinfect the air by deactivating certain microorganisms and pathogens. The UV light works by fundamentally altering the DNA of these contaminants, effectively removing them from the air and improving air quality before pushing it back into your home.
There are three main types of ultraviolet (UV) light: UV-A, UV-B, and UV-C. All three types can be harmful in certain situations.
UV-A light has a wavelength of 320-400 nanometers and is not visible light. It has a lower frequency and vibrates slower than UV-B and UV-C light. Under the right circumstances, UV-A light can effectively break down some organic molecules, including certain airborne pathogens.
However, UV-A light is not typically used in air purifiers because it is less effective at disinfecting air than UV-C light. UV-C light has a shorter wavelength and higher frequency, which makes it more effective at breaking down the DNA and RNA of viruses and bacteria.
UV-B light is an ultraviolet light with a wavelength between 280-315 nanometers. It is not visible to the human eye and is known to cause sunburn and skin damage.
While UV-B light is not typically used in air purifiers for air disinfection, it can still play a role in certain applications like water purification and sterilization.
The effectiveness of UV-B light in air purification depends on various factors like the intensity of the light, the length of exposure time, and the type of microorganisms or pathogens being targeted.
UV-C light ranges from 100 to 280 nanometers in wavelength. It has the fastest vibration and highest energy of all the UV wavelengths.
Due to its strong ability to kill microorganisms, it’s commonly used in sterilization processes, and almost all UV air purifiers use UV-C light. While UV-C air purifiers can be effective at purification and removing contaminants, prolonged exposure to UV-C light can cause skin and eye damage. It’s always important to use your UV-C air purifier cautiously and follow the manufacturer’s instructions carefully.
The technology is also referred to as UV germicidal irradiation, so these purifiers may also be called UVGI air purifiers. UVGI stands for ultraviolet germicidal irradiation.
Effectiveness At Removing Different Pollutants
UV air purifiers are designed to deal with a number of different contaminants. However, they are more effective against some than others:
UV Air Purifiers Vs. Allergens
UV air purifiers are often marketed as a solution for allergies. They claim to help deal with airborne allergens like mold, dust, pet dander, and cigarette smoke. Unfortunately, while UV air purifiers can effectively deactivate these allergens to an extent, they can’t remove them entirely. And some dangerous gases are impervious to UV light, so UV air purifiers aren’t effective against them.
Also, while mold can be deactivated by UV light, it can still trigger allergic reactions in some people. Therefore, while UV air purifiers can have an impact against allergens, they don’t really solve any problems for those with severe allergies.
UV Air Purifiers Vs. Microorganisms
Viruses and microorganisms can be harmful, and many people buy UV air purifiers to remove them. However, while the UV light in air purifiers may deactivate some microorganisms, most common bacteria require prolonged, intense bursts of UV light not achievable with an air purifier.
Air purifiers can be effective at removing viruses. However, the level of reduction will vary depending on the specific air purifier and the type of virus in question. While UV air purifiers may improve air quality, you should understand their limitations and use them with other air purifying measures, like a cleaner with a HEPA filter.
UV Air Purifier Vs. VOCs
Volatile organic compounds (VOCs) are often found in cosmetics, paint, and cleaning products. However, UV air purifiers are not effective at removing VOCs at all, as VOCs are gaseous and do not respond to UV-C light.
To remove VOCs from your indoor air, it’s essential to choose an air purifier that specifically targets these air pollutants, like one with an activated carbon filter, HEPA filter, or a specialized VOC filter. You should also address the source of VOCs in your home by using non-toxic and low-VOC products and improving your ventilation.
What REALLY Does Work? HEPA Filters
To me, when it comes to air purification, nothing beats a HEPA filter. While UV light air purifiers have gained popularity in recent years, they may not be the most effective option for capturing viruses.
One thing that many high-quality air purifiers have in common is the use of HEPA air filters. HEPA air filtration systems are designed to capture tiny airborne particles, including viruses as small as 0.3 microns, with an efficiency of up to 99.97%. This makes HEPA filters an excellent option for trapping viruses and other contaminants in indoor and outdoor air.
Activated carbon filters can absorb harmful gases and chemicals in the air, improving air quality. Combined with a HEPA filter, an activated carbon filter can provide a comprehensive solution for purifying the air in your home.
There are even purifiers now that combine HEPA filters with UV light technology that give you the best of both worlds.
While UV light air purifiers may have their benefits, it’s important to prioritize air purifiers with HEPA filters and activated carbon filters for optimal air purification. Investing in an air purifier with these features can help ensure that the air in your home is as clean and healthy as possible.
Do UV lights kill viruses like COVID-19?
UV lights in air purifiers cannot kill viruses like COVID-19. Even purifiers marketed as ‘COVID-19 ready’ cannot provide sufficient exposure time to effectively neutralize COVID-19 pathogens.
Do UV lights kill mold?
UV lights can kill mold. A UV lamp will help prevent the growth and spread of mold by deactivating mold spores and preventing them from reproducing. However, mold particles can still trigger allergies even if they are no longer viable or able to reproduce.
Are UV air purifiers safe or dangerous?
UV air purifiers can be dangerous. Most UV air purifiers may produce ozone as a byproduct of UV-C technology, which can be harmful if exposed to it in high concentrations. Ozone can cause respiratory irritation and exacerbate existing respiratory conditions.
Do hospitals use UV light to sanitize?
Hospitals have used ultraviolet (UV) light as a cleaning tool for decades. UV light has germicidal properties that can sterilize surfaces, air, and water. As a result, UV lamps are often used in hospitals to disinfect surfaces and equipment in patient rooms, operating rooms, and other areas.
How much does it cost to install UV light in HVAC?
The cost of a UV light for an HVAC system can vary depending on the light’s type and quality, the system’s size, and installation costs. The estimated cost range is typically between $500 and $800.
Which is better, UV light or an air purifier?
Air purifiers are typically better than UV light. UV lights may be more effective at neutralizing pathogens, but air purifiers with HEPA filters are more comprehensive in their ability to filter a wide range of particles, including viruses, bacteria, allergens, and pollutants, which makes them a more comprehensive option for air purification.
So, if you ask me if UV air purifiers are worth it, right now I’d say no. While UV air purifiers have potential, it’s important to note that they may not be the most effective option for capturing a wide range of airborne particles.
On the other hand, you can’t beat a HEPA air purifier. They are designed to capture particles as small as 0.3 microns with an efficiency of up to 99.97%.