Ventilation and Covid-19: The HVAC Angle

Data Shows That Ventilation Works in Preventing Infection

We don’t need to remind you that it’s been an unprecedented time in here in the Southland. Lockdowns, illness, fear, and even rage over all of the above have become mainstream in the past year and a half. We don’t pretend here at Air-Tro to have all the answers. To be honest, we’re all about heating and air conditioning. We’ll happily leave the debates and the politics to someone else!

Nevertheless, this virus that has affected every single person on this planet in one way or another comes with an HVAC element. In fact, it’s this very factor that interests us so much, and why we’re sharing it here.

In late May 2021, The Economist magazine came out with a fascinating article about ventilation and its role in spreading Covid-19. It uses as an initial example of its main premise a group of Chinese families, dining together on January 24, 2020, in Guangzhou. As it turned out, ten of the 21 people at that special Chinese New Year meal became ill with Covid. They did not sit close to one another; indeed, many did not even know each other. Their only commonality was that they were indoors at the same time in this restaurant.

The incident became known as the first “superspreader event” of the pandemic. It puzzled scientists because common wisdom dictates that only people within a certain distance of one another can “catch” a virus from the other person. In other words, if you cough at one end of the supermarket, you shouldn’t be able to infect someone standing on the other side of the building. But in this situation, the disease spread far beyond conventional expectations. Indeed, the situation seemed to contradict WHO’s assurances that the risks of infection from aerosols were minimal. Disinfecting countertops and double washing forks was instead the answer to preventing disease and stopping the spread.

The evidence we have now does not bear that out. As The Economist explains, “the movements of virus-laden aerosols around the three affected families of diners [in Guangzhou] matched the seating positions of the people who eventually became sick. The outbreak occurred because there was no source of external fresh air and a nearby recirculating air conditioner redistributed aerosols from the infected person to the other tables, creating a contaminated bubble of air that was increasingly burdened with viruses over the course of the lunch.”

In other words, fresh air in your home and your building matters enormously when it comes to keeping people safe and healthy, not just from Covid-19, but other illnesses too. As Dr. Lidia Morawska of Queensland University of Technology, Brisbane, Australia, says, “Before this pandemic, it was completely socially acceptable to come to the office coughing, sneezing, spreading viruses around. No one would say anything—even people educated to understand how infections are transmitted.”

Things have changed. We have changed, as people, as a community, and as a nation. HVAC has never been more relevant or important, not just to keep people comfortable, but to keep them safe.

Need HVAC for your home or business? Call Air-Tro. We’ve been the family-owned HVAC company keeping Los Angeles comfortable since 1969.