New CDC release on COVID-19 and Potential Airborne Transmission

Yesterday, the Centre for Disease Control (CDC) released an updated brief on SARS-COV-2 (the virus that causes COVID-19) and potential airborne transmission.

The most significant update is the confirmation that “pathogens…can sometimes also be spread via airborne transmission under special circumstances.”   The briefing describes three circumstances where there appears to be airborne transmission:

  • Enclosed spaces within which an infectious person either exposed susceptible people at the same time or to which susceptible people were exposed shortly after the infectious person had left the space.
  • Prolonged exposure to respiratory particles, often generated with expiratory exertion (e.g., shouting, singing, exercising) that increased the concentration of suspended respiratory droplets in the air space.
  • Inadequate ventilation or air handling that allowed a build-up of suspended small respiratory droplets and particles.

In terms of prevention, the CDC has now added, “ventilation and avoidance of crowded indoor spaces are especially relevant for enclosed spaces, where circumstances can increase the concentration of suspended small droplets and particles carrying infectious virus.”

BC Comfort’s recommendation is to follow ASHRAE’s guidelines for COVID19 prevention:

  1. Increased Ventilation – increasing outside air rates
  2. Increased Filtration – using higher efficiency filters (e.g. MERV13)
  3. Air treatment – UVC treatment

For more information, please contact your account manager at BC Comfort.

SOURCE: https://www.cdc.gov/coronavirus/2019-ncov/more/scientific-brief-sars-cov-2.html, https://www.ashrae.org/file%20library/technical%20resources/covid-19/ashrae-covid19-infographic-.pdf