The ins and outs of mask wearing, as directed by SA Health and police

As of midnight, all South Australians outside home are asked to wear a mask. Here are the right kinds.

Police have urged South Australians to wear masks in public to prevent COVID-19 droplets cross infecting people, and although less effectively, to stop people inhaling the virus.

Police Commissioner Grant Stevens said there were substantial supplies of face masks in South Australia and the logistics of distributing these across were being worked out.

“At this point in time it’s where possible you should wear a face mask,” he said.

Masks are not yet mandatory but panic buying began soon after the lunchtime news conference recommended they be worn.

SA Health has issued this advice to direct the proper use of face masks.

Tests have shown bandannas and scarfs are less effective in stopping COVID-19.

Research published in AIP Physics of Fluid found properly-fitted cloth face masks were better at stopping water droplets from an uncovered sneeze or cough than bandannas or handkerchiefs.

The study tested the effectiveness of handkerchiefs, homemade masks and commercial cone masks.

The stitched, homemade quilting cotton mask was the most effective, followed by the commercial mask, the folded handkerchief, and, finally, the bandana.

Results from the handkerchief test found water droplets pushed forward through the protective barrier and lingered in the air.

Forward projections didn’t occur as much with either the home made or cone masks, but water particles did escape through the gap near the top of the mask.

Surprisingly, water particles from an uncovered cough were found to travel up to 12 feet (3.66 metres) — which is more double the recommended length of social distancing in Australia and the United States.

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