COVID-19 Air System Changes
Many of our clients have been asking for advice on how to reduce the potential for aerosolized COVID-19 transmission. Recent studies and articles have highlighted the potential dangers of aerosolized COVID-19 transmission through HVAC systems.
Our engineers have stayed abreast of the latest guidance from the CDC [1] and ASHRAE [2] detailing how facilities should reduce the spread of airborne pathogens through HVAC systems.
There are four key steps we recommend taking before making large investments in new technologies. There are a number of vendors and service providers that are pushing un-proven or un-related technologies. Instead of speculative or tangentially beneficial technologies, we have been consistently recommending the following four changes to our clients because they are recommended by ASHRAE and the CDC and are largely achievable using existing systems:
Increase the percentage of outdoor air – Both the CDC and ASHRAE recommend increasing outdoor air ventilation by as much as possible. This can be achieved by increasing the number of air exchanges and/or opening outside air dampers to the greatest extent practicable.
Improve central air filtration – The CDC recommends increasing air filtration to as high as possible without significantly diminishing design airflow and inspecting filter housing and racks to ensure appropriate filter fit and minimize filter bypass. ASHRAE has specified improving central and other HVAC filtration to MERV-13 (based on ASHRAE 2017b) or the highest level achievable.
Add ultraviolet germicidal irradiation (UVGI) devices – Both the CDC and ASHRAE recommend UVGI devices as a supplemental technique to inactivate potential airborne virus in the upper-room air or ductwork.
Control space temperature and humidity - ASHRAE recommends that moderate indoor space temperature and humidity be maintained across seasons
If you would like to talk about specific air quality improvements for your facility, schedule an appointment with an engineer.
[1] CDC Guidance - https://www.cdc.gov/coronavirus/2019-ncov/community/office-buildings.html
[2] ASHRAE Guidance - https://www.ashrae.org/file%20library/about/position%20documents/pd_infectiousaerosols_2020.pdf