ASHRAE is keeping pace with the COVID-19 HVAC learning curve with updated guidance to address changing conditions and situations. A newly refreshed edition of the ASHRAE Epidemic Taskforce’s Building Readiness Guide provides more resources for calculating the effectiveness of building flushing and filtration, helping building operators navigate the complexities of clearing contaminants and preparing for incoming occupancies.
“New information includes: the theory behind the use of equivalent outdoor air supply; method for calculating the performance of filters and air cleaners in series; and filter droplet nuclei efficiency that help evaluate the system’s ability to flush the building,” reports Wade Conlan, team lead for the project.
A downloadable program allows operators to enter information about key system elements such as air handling units, cooling coils, filters and in-room air-cleaning device in order to determine the required flushing time. There is also new guidance related to heating wintertime outdoor air and its potential impact on building systems.
This augments the Taskforce’s existing guidance on increased filtration, air cleaning strategies, domestic and plumbing water systems, and overall improvements to a system’s ability to mitigate virus transmission.