When many Australians transitioned to working from home, buildings in metropolitan hubs and regional centers were left empty and their heating, ventilating, and cooling (HVAC) systems put into hibernation. As restrictions ease and workers return to the office, building systems must be considered as part of a safe return by building managers.
“It’s positive to see restrictions lifting and buildings occupied again. We know there is a lot to be considered when returning to a building, but it’s important environmental health is one that is not overlooked,” says Adrian O’Connell, chief executive officer of Standards Australia.
The Australian and New Zealand standard AS/NZS 3666, “Air-handling and water systems of buildings—Microbial control” is a useful tool that helps manage building air quality and risk related to hazards like legionella.
“Precautions should be taken, and regulations and standards considered when preparing the space for returning occupants,” says Nicholas Burt, chief executive officer of the Facility Management Association of Australia.
“A few months ago, many buildings were effectively put into hibernation and their HVAC systems shut down. With two legionella outbreaks already taking place earlier this year, the risks associated with turning these systems back on are very real. The good news is there are practical steps that can be taken to safely flush them out,” says Tony Gleeson, chief executive officer of the Australian Institute of Refrigeration, Air Conditioning and Heating (AIRAH).
Important steps to consider when flushing building systems can include:
- Prior to facilities being opened for use, all water outlets should be flushed for at least 3 minutes each.
- Prior to using appliances such as drinking water fountains, open fixtures to flow for at least a half minute.
- Prior to start-up of any cooling water system, a cooling tower cleaning should be conducted, and care must be taken to disinfect all system water.
- Legionella testing may be conducted to ensure pipework has not been colonized by Legionella during periods of stagnancy.
“The transition of working from home to back to office will have its challenges for many organizations but having a prepared building does not have to be one of them,” concludes O’Connell.