- Before workers return to buildings that have been unoccupied during lockdown, experts warn of a need for them to be properly prepared and safely flushed out.
- Potential dangers from systems being put into hibernation for an extended period can include health risks associated with air quality and mould, microbial growth, and corrosion in water systems.
- The AS/NZS 3666 standard series can be an important tool in assisting building managers and owners to properly flush out their systems and get buildings prepared for thousands of returning workers.
When many Australians transitioned to working from home, buildings in our metropolitan hubs and regional centres 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,” said 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 standards series 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,” said 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,” said 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 clean should be conducted and care must be taken to disinfect all system water.
- Legionella testing may be conducted to ensure pipework has not been colonised by Legionella during periods of stagnancy.
“The transition of working from home to back to office will have its challenges for many organisations but having a prepared building does not have to be one of them,” concluded Mr. O’Connell.