It’s important to understand how aerosolized coronavirus transmission indoors impacts IAQ in buildings and what building and facilities managers can do about it.
We know that the coronavirus gets spread through tiny airborne droplets of water. This happens when an infected person sneezes, coughs or even breathes. The virus also gets transmitted through contact with hard surfaces, such as door handles, light switches, and countertops, but can the coronavirus attach itself to particles already in the air? There is an increasing amount of evidence to suggest that this is the case.
Aerosol Transmission of Coronavirus
The coronavirus gets dispersed by mouth in droplets of water. Some of these droplets are microscopic while others can be the size of a grain of sand. Up to 30,000 particles can be cast from a single sneeze or cough. These droplets also get dispersed when we speak, talk, and breath, and they travel at speeds up to 60 miles per hour. They attach to aerosols, such as dust particles, already present in the air. If the coronavirus is transmitted by aerosols, as the science suggests, this increases the risk of indoor transmission.
Coronavirus Transmission Indoors
Aerosols are clusters of tiny particles that are light enough to float in the air. They contain either solids or liquids. The smaller the particle, the longer it remains suspended in the air. While aerosols are a fact of life, during a pandemic their impact becomes much more serious. Since aerosols stay in the air for up to eight hours, their chances of inhalation by building occupants are increased.
It isn’t known for certain how many pieces of the virus might travel in an aerosol produced by coughing or sneezing. One study currently under peer review suggests that one person speaking in a room could release over 100 infectious doses in a single hour. Since particles can be inhaled by other individuals from up to six feet away, the consequences are serious. Contact with hard surfaces also poses a risk for contracting the virus.
Another study found that coronavirus remained viable in an aerosol for up to three hours. This is about the same amount of time it could take the building’s ventilation system to remove an aerosol from the occupied space.
There have been many studies on how HVAC systems contribute to the spread of microbes in the occupied space. This makes the need for properly functioning HVAC systems critical in limiting the coronavirus transmission indoors.
For the general public, masks are a way to reduce risk because they block aerosols from leaving an infected person’s mouth. Avoiding crowds and practicing social distancing is important as well. Frequent hand washing and following the guidance of public health officials is recommended. In the workplace, strategies for stopping the spread of the coronavirus is essential for building managers.
Pure Air Controls has emergency response solutions to help buildings and campuses lower the risk of the spread of coronavirus. Our decontamination protocols address both the occupied space and HVAC systems. We are an IAQ and HVAC system-focused company in operation since 1984. For more information or to get started with building decontamination please call 1-800-422-7873 or email us.