Improved the ventilation in nursing homes could be a significant mitigating factor in coronavirus infection control, Australian building design and materials experts say.
Many areas of typical eldercare facilities, including corridors and large common spaces, are not directly ventilated or are very poorly ventilated, wrote architect Geoff Hanmer, University of Adelaide, and biomaterials scientist Bruce Milthorpe, University of Technology Sydney, in The Conversation. Wide corridors that allow beds and wheelchairs to negotiate freely enclose a large volume of air, and windows in the residents’ rooms only indirectly ventilate this large space, the authors wrote.
“If the windows to residents’ rooms are shut or nearly shut in winter, these buildings are likely to have very low levels of ventilation, which may contribute to the spread of COVID-19,” they said.
Good ventilation has been associated with reduced transmission of pathogens. And scientists suspect that the virus that causes COVID-19 can be transmitted as an aerosol as well as by droplets. But nursing home operators can take steps to achieve adequate ventilation, starting with the relatively inexpensive purchase of an air quality detector that can reliably measure CO₂ levels, Hanmer and Milthorpe wrote.
“If levels in an area are significantly above 600 ppm over five to ten minutes, there would be a strong case to improve ventilation. At levels over 1,000 ppm the need to improve ventilation would be urgent,” they explained.
The ideal solution is to create a flow of warmed and filtered fresh air from the central corridor spaces into rooms and out through windows. This likely would require an investment in mechanical ventilation.
The authors also suggest creative temporary solutions. Those include using industrial heating fans and a flexible ventilation duct from an open window to discharge fresh air into central corridor spaces. They also recommended radiant heaters in rooms (instead of recirculating heat pump air conditioners) and — in warm weather — windows opened far enough to lower CO₂ levels consistently below 850 ppm in rooms and corridors.