Commercial HVAC and the Coronavirus
Right now there is a world epidemic going around with the Coronavirus. This is a new airborne virus that we are still learning about. We currently know that it spreads through person-to-person contact. Between people who are in close contact with one another (within about 6 feet) and through respiratory droplets produced when an infected person coughs or sneezes. These droplets can land in the mouths or noses of people who are nearby or possibly be inhaled into the lungs.
HVAC Prevention Solutions
The recently reaffirmed ASHRAE position document on airborne infectious diseases, available along with other references here, identifies three demonstrated methods of controlling airborne infection that have proof of efficacy: ventilation, particle filtration, and UV.
ASHRAE has also made available their recently approved position document on Airborne Infectious Diseases. The Society’s position is that facilities of all types should follow, as a minimum, the latest practical standards and guidelines.
Filters
Some air filter manufacturers are testing their consumer-grade products (HEPA filters) against COVID-19, and the results have been promising. One thing to keep in mind, though, is that while HEPA filters may trap the virus, it won’t be destroyed. Instead, it will “remain alive inside the filter for as long as the virus survives.” In some cases, this can be for as long as nine days.
UV Lights
UV lights might be the most effective solution in combating the coronavirus. While filters can capture most of the infectious microbes before they pass, there are still some that get through these filters.
Airborne droplets containing infectious agents can remain in room air for six minutes and longer. Scientists have found that COVID-19 can remain infectious on surfaces at room temperature for up to nine days, this includes the air filters and coils in your HVAC system.
However, UV light applications and fixtures can destroy those microbes when they are exposed to the UV energy in a matter of seconds. Kill ratios up to 99.9% and concentrations are further reduced each time the air circulates.
To learn more about how UV lights kill this virus, click here.
