Bob F explained :
On 6/29/2020 9:30 AM, Bob F wrote:
On 6/29/2020 3:42 AM, FromTheRafters wrote:
It happens that Bob F formulated :
On 6/28/2020 7:26 PM, micky wrote:
The cashier at the supermarket wears a black mask with what looks like
one of these on either side. Like the seashell from Shell gas stations.
I had hoped it was decoration, but it looks like these enough I think
it's just an "activated carbon filter".

https://www.amazon.com/Activated-Fil...tag=mozilla-20


Not only that, she talks low enough I've had to lean over once to hear
what she says.* "The self-checkout scanners are not on. " I knew that.
If they were on, that's where I'd be.

One comment:** they are directional in that you can aim the exhaust some
what. Mine are pointed down and back towards my shoulders.

But these valves are meant to make breathing out easier, right? while
using the rest of the mask to filter the air that comes in, right?* It
seems that vents like this defeat the so-called goal of masks, to
protect the other people.


The valves make them useless for protecting others, so they offer little
aid in reducing spreading.

I read that they are not even recommended as PPE if they have the exhaust
vent. I supposed they do get used for some as PPE to avoid excessive
fogging of face shields or goggles.

They are high performance DUST masks. Nothing more.

I did see a lot of coverage showing these masks in the ER on occasion. It
could be the Doctors taped off the valve to disable it.

Those masks are not to protect others as much as they are to protect
the wearer. Early on I read that even the PPE masks with exhaler ports
are not recommended for this application.