Air conditioners and fans function by moving air around rooms within a home, office, restaurant, or other enclosed space. Since COVID-19 is an airborne virus that spreads from one person to another through contaminated droplets, concerns have been raised about the possibility of the disease spreading by means of AC units.

In an early-release letter, the Center for Disease Control and Prevention studied an instance of COVID-19 outbreak at a restaurant in Guangzhou, China. The letter details the events of the night of January 23, and centers around a 63-year-old woman sitting at “Table A” within the restaurant. This woman was an asymptomatic carrier of the COVID-19 virus. Soon after the evening she spent at the restaurant, 9 other patrons were infected with coronavirus. This led scientists to believe the AC in the restaurant to be the cause of this spread.

This study proved that increased airflow within a room can cause droplets from an infected individual to travel farther than they would normally. This is why restaurants, offices, and other places of business are enforcing the wearing of masks and practicing social distancing. However, there are several benefits to having an air conditioner. In order to mitigate the spread of the virus in your own home, it is important to understand how a virus interacts within an enclosed space and how an AC unit affects that.

The relationship between the virus and your air conditioner.

The coronavirus is expelled when we sneeze, talk, cough and breathe. When we cough, we release 3,000 droplets (particles that contain mostly water, but also any infectious pathogens), while a sneeze can release about 30,000. If a person in your home has contracted the virus, they will be releasing these respiratory droplets into the air surrounding you. Research shows that the virus can live in the air for up to 3 hours. Most American homes utilize central air conditioning systems, which means there is no outside air being used to cool the home. This makes it impossible for contaminated air to enter your home from the outside through the AC unit. 

If the infected person lives in your home, there is a good chance your lungs will breathe in the infectious air. This is possible even if visitors are asymptomatic carriers, as shown in the aforementioned CDC study. However, there are two functions of air-conditioning systems that are a significant part of preventing the infection from spreading:

  1. Ventilation is a key part of an air conditioner as it exchanges the air in a space with high indoor air quality. This system will prevent infection by removing air from a room where there are virus droplets.
  2. When the expended air is brought into the ventilator equipment, the air passes through a filter, removing particulates and other contaminants from the air. Filters will not only trap and hold the virus, but also stop dust and dirt. 

Experts believe if the restaurant in Guangzhou, China had a well-functioning air-conditioning system that provided adequate ventilation and had stronger filters, then the virus would have spread to fewer diners. 

Other factors you should consider.

Open your windows. It is important to increase the amount of outside air being brought into an enclosed space. Opening a window will create better airflow lowering the possible concentration of infectious droplets inside the room.

Consider buying a humidifier or an air purifier. These disinfectants use a filter to capture 99% of particles.

Upgrade filters in air conditioning systems. As a filter catches the natural particulate pollution in your home, over time, the particles will begin to foul up the machinery causing the filtration to be ineffective. Switching to more efficient filters will remove pollutants as well as protect the equipment. However, do not be fanatical about replacing filters. As dust accumulates, the filters get more effective over time.

Do not turn off the AC. Especially in the summer, high temperatures will cause thermal stress and will lower an individual’s resistance to the virus. A virus’s ability to spread increases as temperature decreases. Therefore, it is a good idea to keep your home warmer than you might like it. 

Follow the CDC’s golden rules regarding social distancing and hygiene! 

If you or someone in your household is concerned about the spread of COVID-19 throughout the home by ways of the AC unit, contact TemperaturePro today for a routine inspection or AC tuneup service, or to learn more about Indoor Air Quality products!