International. As many buildings are preparing to reopen during this pandemic, the ASHRAE Epidemic Task Force has updated its "Building Readiness" reopening guidance for HVAC systems to help mitigate SARS-CoV-2 transmission.
"The Building Readiness Guide includes additional information and clarifications so that homeowners can avoid operating their HVAC systems 24/7," said Wade Conlan, asHRAE Epidemic Task Force Building Readiness Team leader. "By implementing this updated guidance, we hope to provide a stronger structure for building owners to complete the objectives of their Building Readiness Plan and anticipate the needs of building occupants."
Updated recommendations specific to the building readiness guide include the following:
- Pre- and post-discharge strategy: The intent of this strategy is to ensure that ventilation helps remove the biological load during, before and after the occupation of the building. The building is washed for long enough to reduce the concentration of infectious particles in the air by 95%. For a well-mixed space, this would require three air changes of the building volume based on cfm of outside air (or three equivalent air changes, including the effect of filtration and air filters) as detailed in the calculation methodology. There are also some guidelines on methods to potentially increase the amount of outside air introduced by the systems.
- Operation of ventilation systems with energy recovery (ERV): helps determine if your energy wheel is well designed and / or well maintained and if it should remain in operation. Please note that if any issues are fixed, you may be able to reconnect. Useful links and information to the ERV Guide that will help homeowners determine if their power wheel should remain in operation.
- Modes of operation of preparing the building for the building: These should include the following:
* Epidemic On-Site Operating Conditions (ECiP)
- Busy - in pre-epidemic capacity
- Occupied - at reduced capacity or Temporarily unoccupied
- Operation during the closure of the building indefinitely
* Post-epidemic conditions at the site (P-ECiP)
- Before occupying
- Operational considerations once occupied
The guide still addresses tactical implementation and systems analysis to develop a Building Readiness Plan, increased filtration, air cleaning strategies, domestic water and plumbing systems, and general improvements to the systems' ability to mitigate virus transmission.
To view ASHRAE's complete building readiness guide and other COVID-19 resources, visit ashrae.org/COVID-19.
