Now that summer is here and the weather’s getting hotter, one question that people are Googling is, “Does air conditioning spread coronavirus?”
This is a topic that interests scientists, who have been carrying out research into whether an AC unit has any effect on passing on, or curtailing, COVID-19. This all depends on the type of air conditioning you have installed.
The only way air conditioning could spread the virus would be with the kind of unit that simply moved the air around the house rather than bringing in fresh air from outside. Air conditioners that cycle out the indoor air, exchanging it with outside air, help to lower transmission by removing air that might be contaminated.
Understanding your AC system
You should identify if your AC unit is a heating, ventilation and air conditioning (HVAC) system that cycles air from outside. A fresh air intake unit will add fresh air to your home through the heating and cooling system. This will improve the indoor air quality by diluting stale or polluted air and pressurising the home to help keep pollutants out.
The majority of residential systems use an HVAC air handler fan to draw in fresh outside air from a duct in the wall or attached to the foundation vent. The fresh air is filtered before it enters the air handler. It then mixes with the return air and disperses evenly throughout the building via the supply duct system. Clean air enters the duct before the air handler fan, reducing the volume of return air that’s pulled from inside the property.
Due to the fact the supply air exceeds the return air, the positive pressure is maintained indoors when the HVAC system is operating. This reduces the number of irritants and pollutants that get inside.
Keep your home ventilated
A well-ventilated environment makes it harder for the coronavirus to spread and is therefore important for any business or public indoor area that has high traffic.
Research by the Harvard School of Public Health suggests the HVAC should be leveraged to minimise the risks of airborne transmission. This can be done by fitting it with high-efficiency filters which strain particles of pollutants out of the air.
The American Society of Heating, Refrigerating and Air-Conditioning Engineers has set up a coronavirus task force. Their research suggests that poor ventilation in a property enables any contaminant lingering in the air to potentially become a threat. It’s important for particles in the air to escape, or to get diluted, using a high-quality AC system.
COVID-19 guidance document
The Federation of European Heating, Ventilation and Air Conditioning Associations has drafted a guidance document on how to cope with the potential spread of COVID-19 when it comes to office premises.
The organisation suggests keeping the AC on at a low setting 24/7 if possible, or turning it on two hours before the workforce arrives and leaving it on for a further two hours after everyone has left for the day. This will help to ensure particles are removed out of the building.
The general recommendation is to stay away from offices which are overcrowded and poorly ventilated, as people must still practice social distancing and other safety measures outside the home, despite the lockdown restrictions being relaxed slightly.