Last week, Governor Cuomo announced that malls in New York could not reopen until they installed high-efficiency particulate air filters capable of trapping the virus that causes Covid-19. This announcement comes after months of speculation about the role that airborne particles play in the transmission of the virus.

If the evidence continues to point to COVID being airborne, it’s likely that other states will follow New York’s example in requiring high-efficiency air filters in indoor public spaces.

Is COVID actually airborne?

While initial studies seemed to suggest that COVID was spread primarily through large droplets, there is increasing evidence that aerosols play a role in transmission.

Aerosols are tiny bits of particles that can be generated by people talking, breathing, or singing. They’re much smaller than large droplets and have the ability to travel further and linger longer in the air.

Donald Milton, a professor of environmental health at the University of Maryland who studies how viruses are transmitted, has helped lead a group of 239 scientists to research the potential airborne transmission of COVID. The scientists explained that multiple studies have shown that aerosols containing small particles of viruses can remain in the air and infect people farther than 6 feet away.

How can air purifiers help reduce infection rates?

If the virus is indeed lingering in the air, it has the potential to infect anyone who enters the room for a long period of time after it’s been released. Eliminating the virus from the air is key to stopping the spread.

One of the most difficult things about protecting against COVID-19 is that the virus is extremely small, with a diameter of approximately 60–140 nm. Fortunately, a high quality air purifier can filter out particles as small as 1 nm.

Will the New York mandates mean that indoor shopping and dining is safe?

Not necessarily.  Indoor settings such as restaurants, bars, house parties, and places of worship where people may be shouting, talking, or singing for long periods of time have been the primary sources of outbreaks. While air purifiers can be beneficial in reducing transmission, there is still a lot that we still don’t know about how COVID is passed from one person to another.

One of the biggest mysteries is how much dosage and exposure time are necessary in order for someone to become infected. Until more is known about how the virus is spread, it is probably best to continue wearing masks, social distancing and avoiding crowded indoor settings whenever possible.