[sexobon]

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 researchers used a tailored LED lighting system and a high-speed camera to film the dispersal of airborne droplets produced by a healthy person with no respiratory infection, during speaking, coughing, and sneezing while wearing each type of mask.

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. ...

... 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." ...

If Your Mask Doesn't Have Two of These, It's Not Working, Study Says

In the absence of medical grade personal protective equipment (PPE), many of us have turned to homemade cloth masks to help stop the spread of coronavirus. But increasingly, research has shown that not all masks are created equal, and some are downright ineffective. A new video case study produced by Australian researchers shows that in order for a homemade cloth mask to stop viral transmission, it needs to have at least two layers of fabric. In effect, if your mask has just one layer of fabric, you can safely bet that it simply doesn't work. ...

Watch Bill Nye Test Which Face Masks Work the Best
THE SCIENCE GUY IS HERE TO, ONCE AGAIN, EXPLAIN A CONCEPT WITH AN EXPERIMENT YOU CAN DO AT HOME.

... Next, Nye uses a homemade, double-layer cotton face mask with a pipe cleaner insert that allows it to fit snugly over the bridge of the nose. Blowing as hard as he can, just inches from the flame, the scientist is unable to blow it out. ...