Lengthy building shutdowns to help stop the spread of COVID-19 could create friendlier conditions for the bacteria that causes Legionnaires’ disease, new guidance from ASHRAE warns. The Society’s Epidemic Task Force has developed a checklist of measures commercial and institutional building operators should undertake before welcoming back occupants, which includes a recommended brush up on ASHRAE standard 188, Legionellosis: Risk Management for Building Water Systems.
“A decrease in water usage in buildings closed or with limited access during the pandemic can increase the risk of bacteria growth in building plumbing and associated equipment,” an ASHRAE advisory states.
HVAC system maintenance, including filter replacement and complete flushing of indoor air, is also recommended prior to facility reopening. Operators are advised to run exhaust fans and open outdoor air dampers for at least two hours before re-occupancy or, alternatively for buildings that don’t have programmed controls, open all windows for at least two hours.
In turn, tenants should be informed of all measures implemented to prepare for their return. Along with the overview of air quality vigilance, it can include communication about cleaning protocol and instructions about personal protective equipment (PPE) where necessary.
“We have reached a time where planning for a safe return to normal activities has become a priority,” affirms Darryl Boyce, 2019-20 ASHRAE president. “Safe operation of HVAC and building water management systems are critical components of building readiness and reopening, and ASHRAE’s resources provide a framework for developing plans in a variety of building types.”