HVAC Systems – Designing during & after COVID-19
Source: Chad Musselwhite· WILLIAMS ENGINEERING CANADA · | March 17, 2021
Source: Williams Engineering Canada
HVAC systems provide ventilation and air circulation in buildings and play a critical role in indoor air quality. Because of the COVID-19 pandemic, building owners and operators might have concerns about their building’s HVAC system and its effectiveness. As a building owner or property manager looking to re-open a building, you want to ensure that the HVAC system is working effectively to provide the healthiest possible indoor air quality for building occupants.
Are current HVAC systems adequate to help prevent the spread of airborne diseases?
There are so many factors to consider that there is not a one-size-fits-all answer to this question. Every building is different and serves a unique purpose. The types and ages of HVAC systems vary widely and will also operate differently from building to building. For example, a hospital or emergency response facility will require more advanced ventilation and filtration than a walk-up apartment building, school, retail facility, office building, or fitness centre. To the extent that an HVAC system can provide additional clean, fresh air, more complete distribution of that fresh air, and offer optimized space temperature and humidity, it will support better health outcomes for those who use the facility.
HVAC system design is just one part of the strategy
A building’s HVAC system design and operation is only one part of the strategy for preventing the spread of airborne viruses in an indoor environment.
Other considerations include:
The type of virus and its primary modes of transmission.
Building occupancy levels. How many people will be in the building during and after the pandemic?
How people use, move through, and congregate in the building. For example, a learning institution will require a different strategy than a supply warehouse.
The development and implementation of other mitigation strategies. These include mask-wearing, the distance between workspaces, and hand sanitation.
How can HVAC system design contribute to preventing the spread?
The HVAC systems help set the scenes where people live their lives at home, at work, and at play. When those environments contain clean air and optimal temperature and humidity, two things happen. First, the growth and viability of viruses, bacteria, and molds are discouraged or suppressed. Second, the baseline resilience of occupant immune systems is actually bolstered, improving their health outcomes even if they have become infected within the building or elsewhere.
Key things to look at include fresh air intake quality and quantity, air circulation, airflow patterns, humidity, and temperature. Depending on the function of your building, you could also consider air filtration or air treatment strategies.
Let’s look at some key points that building owners and property managers can investigate further to ensure their HVAC system operates adequately and safely.