Over the last year, we have all seen the effects of the Covid-19 virus and the impact that it has had on our daily lives. Responding to this threat has been a challenge, and many people are wondering about the effectiveness of air filtration systems when it comes to removing viruses. In this article, we will take a look at some of the advanced air filtration system types and how effective they are at dealing with Covid-19 and other viruses.
Can an Air Filtration System Remove Covid-19?
Before we look at the various air filtration types, let’s examine the efficacy of such systems on Covid-19 or any other virus for that matter. Firstly, it’s important to understand that the only way that any air purification system could remove a virus is if it was already present in the home. So, even if you are being careful and engaging in the best hygiene practices, there is a chance that a virus can enter your home. How? Well, it’s your own lungs that are the problem, people tend to breathe in viruses, and no system is going to clean inside your body or nasal cavities. For this reason, many experts recommend the use of N95 (or better) masks when you’re outside your home. Using hand sanitizer is also a good idea to prevent rubbing microorganisms onto your face.
Now that we’ve covered the best ways to avoid bringing a virus into your home, what do you do if your preventative efforts have failed? A standard air filter fitted to your HVAC system will not be effective at capturing any type of virus. A virus is extremely small, and it can easily pass through standard filter media. But, viruses can be present on the surface of standard filters, and it’s a good idea to wear gloves when you change them. All old air filters should go straight into a sealed trash bag and be removed to your garbage can outdoors.
Let’s take a look at four more advanced air filtration systems and gauge their effectiveness against Covid-19 and other viruses.
- High Efficiency Air Filters
These are air filters that can capture a particle of 2 microns or larger. At this level, they are more than capable of removing most allergens, pet dander, dust particles, and mold. Sadly, a high efficiency air filter cannot remove a virus unless it gets tangled with a direct hit on a fiber which would be a pretty rare occurrence. Most of the virus will continue on through the filter and from there into your air distribution system. Even if you install a true HEPA filter, you can only filter down to 0.3 microns which is equivalent to an efficiency rate of 99.97%. Although this sounds impressive, it still isn’t sufficient to consistently capture a virus that is still too small. When it comes to true HEPA filters, it is true that they are used in hospitals, but medical facilities do not rely on them solely to protect against viruses.
- Electronic Air Filters
An electronic air filter traps particulates present in your indoor air in a prefilter. If any airborne contaminants get past the prefilter they are then trapped in a filter that’s electronically charged. In some models, the filter is composed of a pair of oppositely charged plates, and others use a filter that generates ozone. The ozone generator creates oxygen molecules, which become attached to airborne contaminants and kill them. These types of systems are very effective at dealing with bacteria and mold spores, but how effective are they when it comes to viruses? The Journal of Natural Science, Biology, and Medicine have stated that ozone generates can kill coronaviruses (which should Covid-19). When ozone generators are used on viruses, they typically destroy up to 99% of the cells that make up the virus. But, ozone has not been specifically tested on Covid-19 at this point, and this makes it difficult to make a solid recommendation.
- Ultraviolet (UV) Lights
We have seen the adoption of UV lights to disinfect surfaces and water for some time. It’s known that ultraviolet light can destroy viruses such as MERS and SARS, which are both coronaviruses. But, it can take some time for the ultraviolet light to destroy the DNA sequence of a virus to finally kill it. Although an area bathed in UV light, such as an evaporator coil, is extremely effective, this may not be an ideal way to remove an airborne virus. When a virus is inside your air delivery system, it may be traveling at up to 450 cubic feet per minute! This means that any exposure time to UV would be too fast, and the light would not have time to destroy the virus.
- Air Scrubbers
An air scrubber uses an advanced filtration system that transforms the microscopic water and air molecules in the incoming air into VOC oxidizers. They are then released back into your indoor air, where they attach themselves to contaminants. The contaminants can be airborne or located on surfaces inside your home. Air scrubbers have been extremely effective at killing many types of contaminants, including Swine Flu, Bird Flu, Strep, Staph, E.coli, and more. One of the key advantages that air scrubbers have over the other methods above is that they distribute VOC molecules to attack contaminants wherever they are located. So, as the air is distributed throughout your home via the HVAC system and ductwork, the VOC molecules are hunting contaminants constantly. Although air scrubbers have not been specifically tested on Covid-19 at this time, they are highly effective at killing bacteria, mold, and viruses. But, this effectiveness comes at a price, air scrubbers are expensive systems, and they are often paired with some of the other systems mentioned here for full spectrum protection.
At the moment, we have no advice on any air filtration system that is guaranteed to be effective against Covid-19. This is because no consumer grade air quality systems have been tested for their effectiveness against this virus. Every system we have shown will have some level of effectiveness, but there are other factors to consider. Adding denser levels of filtration can lower the airflow, which may lead to a loss of efficiency and even cause damage to your HVAC system. If you want to learn more about how to protect your home to the best of your ability, contact your local HVAC specialist today.