As Russell Lavitt shared in a recent piece on Facilitiesnet.com, many Facilities Managers (FMs) need guidance on which protocols will increase their HVAC systems' efficacy in mitigating the transmission of viruses and their variants that can hang and dwell in ambient air, such as COVID-19.
The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) has developed guidance for FMs that covers all building types and can be invaluable in identifying AND addressing HVAC system issues in light of the current environment.
Implementation of these protocols and guidelines, along with COVID-19-appropriate screening and cleaning measures, will provide a healthy and safe environment for your employees, clients, and guests. ASHRAE's guidelines recommend four approaches that will improve indoor air quality:
- Dilution: Measures that increase the amount of fresh air introduced into the facility, thereby diluting viral aerosols.
- Filtration: MERV 13, 14, 16 - all the way to HEPA filters will work with your dilution methodology and improve your indoor air quality. If you can use a MERV 16 filter without negatively impacting your airflow - that appears to be equivalent to 100% outdoor air.
- Occupant-based solutions: Implementing policies that define a maximum period of time that occupants can use a specific space (i.e., a conference or breakroom) so as to allow enough time before the next use for the HVAC systems to purge the space and clean the air.
- Portable filtration units: Equipped with HEPA filters, these units can scrub the air at a much greater volume than air handlers are capable of processing.
To better manage your ventilation and indoor air quality (IAQ), apply multiple ventilation interventions, if possible. The more you can implement, the greater chance you have at reducing the concentration of virus particles in the air and reducing the risk of viral spread.
You will want to:
- Increase the introduction of outdoor air (when possible)
- Improve central air filtration
- Add portable filtration options
- Create directional airflow
- Install supplemental air treatments as reviewed, above.
About the author: Russell Lavitt is the Buildings Mechanical Team Lead for Stantec’s Manitoba and Northwest Ontario region in Canada. A licensed professional mechanical engineer, he is an expert in complex and multi-faceted mechanical design, sustainability, and energy-efficient building technologies. We thank him for his permission to share his advice on this topic!