Air purifiers – Killer of Airborne Virus?
The demand for air purifier witnessed a steep hike during this unprecedented crises. The chances of COVID-19 virus to stay in the air for a considerable amount of time has created an enormous momentum for equipment and devices associated with air purification. Although an air purifier has the in-built ability to battle known causes of respiratory problems, thestandard HEPA filter, however does not have the ability to capture and destroy something as small as a virus. It, on the other hand, improves the overall air quality in your home. As per Dr. G.C. Khilnani, PSRI Hospital, Delhi, “The virus is extremely small and isn’t likely to be captured in standard filters. Even an air purifier with PECO filter helps only in a limited way. he method PECO filters implement to tug particles from the air can catch incredibly small items, it is unlikely that it can actually kill the Coronavirus as the novel virus can live on surfaces for an extended period of time.
The Science Behind Air Purifiers
Viruses are roughly 100 times smaller than bacteria, and typically range from 0.004 to 0.1 microns in size. Air purifiers use fans to draw in air and pass it through a filter before expelling the purified air out the other side. They’re particularly effective at removing odors and large particulates from the air. If you suffer from pet allergies, for example, an air purifier can help capture the dander and reduce your symptoms. On the other hand, there is a limit to what an air purifier can capture. Even the most powerful air purifiers can only capture particles as small as 0.1 microns, and the vast majority of air purifiers will only capture particles which are 0.3 microns or larger. This means even the most powerful air filters would struggle to purge a virus from the air. The primary culprits of poor indoor air quality are larger than this size limit; mold, pollen, and pet dander are all larger and can be caught and eliminated by a standard HEPA filter.According to Dr. Arvind Kumar, Chairman, Centre for Chest Surgery and Chest Onco-Surgery and Director, Institute of Robotic Surgery at Sir Ganga Ram Hospital, “The world will face more such pandemic in the times to come and we need to prepare ourselves for it. Now with this climate change and air pollution issue being so glaring and relevant today,we need to make our systems ready for such pandemics; resilient to face the onslaught of such pandemics; able to absorb the shock so that life can go on normally despite this.”
The Major Difference
In order to have a better understanding of the functioning of air purifiers, it is pivotal to understand the difference between air filters, air cleaners and purifiers. While air filters are capable of trapping and collecting dirt and debris in a filter, they are helpful in only reduce the amount of pollutants, allergens and dust in your home. Air cleaners, on the other hand, work more efficiently in eliminating more particulate from the air than the average filter. Air cleaners come with an in-built fan which sucks the air in and the filter works accordingly to remove particulate from that air. This means that air cleaners are better off when it comes to cleaning the surrounding air. Air purifiers has an in-built process to effectively deactivate airborne toxins. Some purifiers in the market also use ultraviolet light sterilization to kill mold and bacteria while others use an electrostatic filter to draw particles to metal plates.
HEPA vs. PECO Filters
HEPA (High-Efficiency Particulate Air) and PECO (Photo Electrochemical Oxidation) are the two primary fabric filters which employ different strategies to remove pollutants from the air.Every HEPA air purification unit boast two primary features- a filter and a fan. It is the fan which is responsible formoving the air through the filter, which further captures pollutants. This one acts a lot like a net to remove pollutants from the air.Very small pollutants, such as volatile organic compounds, may stick to the fibers for a moment but their mass is so low they are dislodged by the air molecules in the passing current from the fan and end up penetrating the filter. PECO-filter works on a different model as it does not depend on friction to catch the pollutants. The fibers of a PECO-filter are properly coated with a nanocatalyst that initiates a chemical reaction to destroy pollutants. The toxic gases and allergens stick to the PECO-filter’s and are then exposed to the chemical reaction to oxidizes them.
The upgraded MERV-13 Filter
As per The National Air Filter Association, a MERV-13 filter is highly efficient in removing 90% of particles between 3 and 10 microns in size, with 85% of particles between 1 and 3 microns in size, and 50% of particles between 0.30 and 1 microns in size. This means that the MERV-13 filter mild hold a chance in filtering viruses out of the air, dependent on the specific virus. However, it is important to keep in mind that a MERV-13 filter is only capable of removing 50% of those particles from the air, and therefore, is not a foolproof method for killing coronavirus.
The Only Truth
The truth, according to Dr. Arvind Kuma is, “Social distancing and lockdowns are the only answer to contain the virus.” It is equally important to protect the environment or future pandemics will shake the world. There needs to be strict enforcements of thermal power emissions norms along with enforcement of construction and solid waste norms. The truth is, we all need clean air to breathe and survive. We all need optimal oxygen levels for our organs to function properly. So, let’s be cautious and fight this together.
