Viruses/Bacteria Air Purifiers

In early 2020, the COVID-19 pandemic has caused people to become more aware of the impact of viruses and infectious diseases because of the dramatic number of infections and loss of human life worldwide.

Viruses vary in diameter from 20 nanometres (nm; 0.0000008 inches) to 250–400 nm with the largest measuring about 500 nm in diameter and about 700–1,000 nm in length. COVID-19 has a size of 60–140 nm with mean size of 100 nm (i.e. nano-aerosol).

The coronavirus is at the lower end of a HEPA filter's range, so it might not be 100% effective on a single pass. HEPA filters are designed to remove at least 99.97% of bacteria and any airborne particles with a size of 0.3 microns (µm). 

A study conducted by Hiroshima University found that using Ultraviolet C light with a wavelength of 222 nanometers which is safer to use around humans effectively kills SARS-CoV-2. The results suggest that UV-C could be used for infection prevention and control against COVID-19.

A combination of HEPA and UV-C light, a long with enough exposure to the UV light in an air purifying device can disable some viruses, including COVID-19.

You may want to consider buying an air purifier if someone in your household is at extremely high risk — either of contracting COVID-19 or of developing complications from it. Our top picks of air purifiers against viruses are below.