Home-made face masks likely need at least 2 layers to curb COVID-19 spread:
Home-made cloth face masks likely need a minimum of two layers, and preferably three, to prevent the dispersal of viral droplets from the nose and mouth that are associated with the spread of COVID-19, indicates a video case study published online in the journal Thorax.
[...] A team of Australian researchers therefore compared the effectiveness of single and double-layer cloth face coverings (175 g/m² cotton fabric, with a thread count of 170/ inch) with a 3-ply surgical face mask (Bao Thach) at reducing droplet spread.
[...] The video recording showed that the 3-ply surgical face mask was the most effective at reducing airborne droplet dispersal, although even a single layer cloth face covering reduced the droplet spread from speaking.
But a double layer covering was better than a single layer in reducing the droplet spread from coughing and sneezing, the recording showed.
This is just one case, added to which several other factors contribute to the effectiveness of cloth face masks, note the researchers. These include the type of material used, design and fit, as well as the frequency of washing.
Nevertheless, based on their observations, a home made cloth mask with at least two layers is preferable to a single layer mask, they say, adding: "Guidelines on home-made cloth masks should stipulate multiple layers."
And they emphasise: "There is a need for more evidence to inform safer cloth mask design, and countries should ensure adequate manufacturing or procurement of surgical masks."
Journal Reference:
Prateek Bahl, Shovon Bhattacharjee, Charitha de Silva, et al. Face coverings and mask to minimise droplet dispersion and aerosolisation: a video case study [$], Thorax (DOI: 10.1136/thoraxjnl-2020-215748)
(Score: 0) by Anonymous Coward on Monday July 27 2020, @05:42PM (3 children)
That's what the supposed media claims. There is more than one media, all of Congress tunes into the classified news where they say don't worry about masks.
(Score: 2) by Tork on Monday July 27 2020, @06:06PM (2 children)
🏳️🌈 Proud Ally 🏳️🌈
(Score: 0) by Anonymous Coward on Monday July 27 2020, @06:25PM (1 child)
The ideal mask lets in germs from others but blocks the outgoing germs. That way you keep your own immune system strong while not posing a threat to anyone.
(Score: 0) by Anonymous Coward on Wednesday July 29 2020, @03:02PM
Except when the disease in question kills you or interrupts your ability to function in a way you can't afford, or you are already immunocompromised for any number of reasons, or you realize that 'ideal' is not possible.
Let's just say you're wrong, OK?