Many people prefer to wear visors than masks as mouth and nose protection.
US researchers have now examined in a study how well these protect against droplet infection.
In
Germany
, there has been
a
mask requirement
since the outbreak of the
coronavirus *,
for example in public transport and supermarkets.
Many people prefer to wear
visors
.
US researchers have now investigated how different
face masks
and
visors
can protect
against
droplet infection
.
Boca Raton / Munich -
Since the outbreak of the
coronavirus
, it has become mandatory to
wear
mouth and nose protection
, for
example in public transport or in supermarkets.
Experts are warning of the
second wave * of
the pandemic.
Many people now prefer to use
visors
than
masks
.
You find this more pleasant.
In addition, the facial expressions behind the transparent plastic disc remain recognizable.
But how well do such
visors
protect
?
Researchers from
Florida Atlantic University
have now used a
video investigation to
test how different
face masks
and
Visors
can protect
against
droplet infection
.
Corona: US researchers are testing the protective function of face masks and visors
The American scientists
Siddhartha Verma
,
Manhar Dhanak
and
John Frankenfield
simulated the emission of droplets when
coughing
and
sneezing
using a special doll.
Using
laser light
in a dark room, they tracked the movement of the artificially produced droplets.
The
researchers
published their results in the
journal “Physics of Fluids”.
Corona: Visors and masks with valves do not protect against the distribution of the droplets
Through the illustration, the
researchers
were able to
observe that the
droplets
initially
spread downwards along
the
visor
, i.e. the forward movement of the exiting air was prevented.
However, the droplets then spread around the
visor
in the room.
Just a few seconds after the simulated cough, a
cloud of droplets
formed in
front of the
face shield
.
A new visual experiment from Florida Atlantic University researchers shows why you shouldn't rely on face shields and face masks with valves.
@ReeveWill reports.
https://t.co/DT0fj3HCZd pic.twitter.com/x8gSK97NI4
- Good Morning America (@GMA) September 2, 2020
The
researchers
found something similar
in
face masks
with a
valve
.
You could observe that the air was
pushed
out
unfiltered
through the openings on the valve
.
The
droplets also
spread out in the room.
Such a
face mask
is therefore not suitable
for preventing
the spread of the
coronavirus *
by an infected person.
The
masks with valve
filter the inhaled air, but not the exhaled air.
Coronavirus: US researchers recommend avoiding visors and masks with valves
According to
the American
researchers
,
visors
and
masks with a valve
are
less effective than
medical masks
and
cloth
masks
for protecting against
infections
with the
coronavirus
.
These were also
tested
in the
video investigation
.
Special respiratory protection masks (N95 standard) and simple cloth masks do not offer 100% protection either, but let through fewer droplets in the experiment.
The
US researchers
therefore recommend avoiding wearing
visors
and
face masks with a valve
, despite the possibly greater comfort
.
Again and again you see people who
only pull
their
mask
over their mouth.
A virologist explains what to think of this application.
In coaches it also happens that the
mask requirement is
ignored.
Product warnings of ineffective
respiratory masks have
already been issued more frequently
.
After the end of the summer vacation, a
mask is required in lessons
in Bavaria's schools
- for the first nine days of school.
(ph / dpa) * Merkur.de is part of the Ippen-Digital editorial network
List of rubric lists: © picture alliance / Jane Barlow / PA Wire / dpa