With masks now mandated in several Australian states to curb the spread of coronavirus, confusion reigns as to whether drivers need to wear their coverings while alone in their cars.
When Greater Brisbane entered a three-day lockdown after a coronavirus case was detected, residents were urged to wear masks whenever they were outside of their homes – including when they were travelling in a car.
"When you leave your household, put [a mask] on and keep it on until you get back home … including in the car," Queensland Health Minister Yvette D'Ath told the ABC.
Minister D'Ath said this was to ensure mask wearing was "as simple as possible for everybody".
Masks are required in cars regardless of whether a driver is carrying passengers or not – meaning those in Greater Brisbane had to mask up even while on the road solo.
These guidelines were a deviation from the advice Victorians received while in the grips of their extended lockdown, when masks were only required in the car if someone from outside your household was present.
"You do not have to wear a face mask when you are in a car by yourself or with someone you live with," Victoria's Department of Health and Human Services declared at the time.
In New South Wales, where a recent COVID-19 outbreak also prompted the government to mandate masks in indoor spaces around Greater Sydney (including Wollongong, Central Coast and Blue Mountains), the rules also didn't require people to wear a mask when travelling in a car alone.
Of course, all three states require masks to be worn in rideshare vehicles such as Ubers, as well as in taxis and on other forms of public transport.
So, is Queensland's approach towards face masks in cars overkill, or just right?
According to Associate Professor Jill Carr, a virologist specialising in Microbiology and Infectious Diseases from Flinders University's College of Medicine & Public Health, there are no clear benefits to wearing a face mask alone in the car unless you plan to carry passengers in the near future.
"In my opinion, no [there are no benefits], unless the driver is only ‘transiently’ alone and is going to be picking someone up along the way, or is going to load the car to someone else to drive later," Professor Carr told CarAdvice.
"This may be the premise of the directive to wear a mask in a car, even if alone – to prevent contaminating the vehicle that someone else may use later."
Generally speaking, the rates of COVID-19 transmission in cars are likely to be higher than in other indoor spaces because of the more compact size.
"There is no opportunity to physically distance," Professor Carr explained. "However, things like making sure a window is open or venting is not on recirculation might be helpful to increase air circulation and reduce risk."
So, is wearing a mask while alone in a car at all helpful or necessary?
"A mask would certainly reduce any infectious droplets contaminating the surfaces in the car, but might not completely prevent this – depending on factors such as the fabric of the mask, how well it fits the wearer, if they are wearing it properly etc," Professor Carr said.
"Fabric surfaces are only infectious in the order of hours but smooth plastic surfaces or metal surfaces can harbour infectious virus for several days."
So, as in the case of many other coronavirus health precautions, wearing a mask while alone in the car may not make a huge difference – but it certainly helps.
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