Since the start of 2020, the whole world has been greatly affected by the pandemic caused by the COVID-19 virus. Millions of people have been infected and the numbers continue to rise. In late 2020, the World Health Organization (WHO) declared that the virus has a potential to spread through airborne transmission. Although there are safety measures in place to fight the spread of the virus, such as social distancing and wearing of masks in public places, particularly in indoor environments, proper maintenance of the HVAC system is also important to help fight the spread of COVID-19.
Inside the air-conditioning units found in every home and establishments is the air filter that performs one of the fundamental responsibilities of the Heating, Ventilation and Air- Conditioning or the HVAC system, which is to clean the air that circulates inside an enclosed space. It separates particles like dust, pollen, dead skin cells, and even smoke particles. But when it comes to viruses, certain improvements can be done in order to increase our chances of stopping the spread of COVID-19.
HEPA Filters – or the High Efficiency Particulate Air Filters, are advanced mechanical air filters which are capable of removing any airborne particles as small as 0.3 microns. For reference, the diameter of a single strand of hair is 25.4 microns.
Initially used in aircrafts and hospitals, HEPA filters are made of a pleated sheet of fiberglass fibers. Instead of sieving, particles in the air that pass through adhere and become embedded into the fibers.
Ionizing Filtration Systems – Ionizing Filtration Systems are composed of two major parts, an ionizing grid and a charged filter. The ionizing grid generates an energy field that blows any debris or particles floating from the air pulled through it. The charged filter then gives the particles a negative charge while the air is being positively charged, completely separating them and cleaning the air.
Ionizing filtration systems are typically more expensive, but they can remove particles down to 0.1 microns, and are therefore generally more effective compared to HEPA filters.
UV Air Scrubbers – Rather than filtering particles from air, air scrubbers function in a different way. UV air scrubbers utilize ultraviolet light to neutralize viruses and other bacteria present in the air.
It works by allowing air to flow through a small lamp that emits UV light which then kills bacteria and other viruses or prevents them from propagating. Unlike the UV light that causes sunburns or skin cancer, UV air scrubbers are totally harmless to people.
Whichever filter type is chosen; the priority is to neutralize the COVID-19 virus. While these filters may not in themselves fully stop COVID-19 spread, they should be part of the solution to help reduce the chances that the COVID-19 virus spreads within the indoor environment.