HVAC Systems and Air Quality
The American Society of Heating, Refrigeration and Air-conditioning Engineers (ASHRAE) has developed guidance for the operation and maintenance of heating, ventilating and air-conditioning systems to reduce the risk of COVID-19.
We will be implementing the recommendations below:
- Keep ventilation systems operating for longer periods of time. Based on this recommendation we will increase operating time. We will run HVAC systems in our buildings for a full two hours before any occupancy in the morning and at all times during occupancy. Overnight we will complete a 2-hour post occupancy purge sequence to flush the building with fresh outside air. We will increase operating time as we progress through our stages with a full 24-hour system operation starting at Stage 4.
- Increase ventilation. We will reset outside air dampers on our systems to a minimum of 50% outside air. This will significantly increase ventilation while still allowing us to achieve required set points for heating. Rooms and areas that do not have working ventilation or an operable window available will be closed for use.
- Disable demand control ventilation and energy recovery systems. We will disable our occupancy sensors and demand controlled ventilation systems that reduce airflow during periods of partial occupancy. Although this will substantially decrease overall efficiency it will keep airflow and outside air high.
- Increase filtration. We will increase our filter change frequency from 3 filter changes per year to monthly filter changes.