“We understand how dangerous a mask can be. We all become what we pretend to be.” (Patrick Rothfuss)
The Centers for Disease Control and
Prevention (CDC) guidance since early 2020 is that everyone (sick or healthy)
wear a cloth face mask in places where it can be hard to stay 6 feet
away from others like grocery stores. People can spread Coronavirus Disease
2019 (COVID-19) even if they don’t have symptoms (called asymptomatic) or
before they have symptoms (called presymptomatic).
When someone who has COVID-19 coughs,
sneezes, or talks, they send tiny droplets into the air, this is where a mask can
help. A face mask covers your mouth and nose. It can block the release of
virus-filled droplets into the air when you cough or sneeze. This helps slow
the spread of COVID-19. Multi-layer cloth masks help block up to 50-70% transmission
of the virus from an infected person.
While a cloth face mask won't totally block COVID-19,
it’s an added layer of protection for you and the people around you. You should
use it along with regular handwashing and social distancing measures like
staying 6 feet away from others. There are 9 types of facial masks listed below
that you should be familiar with:
Bandana: A bandana is a
triangular or square piece of cloth that’s often worn as a head or neck
covering. Tying a bandana over your mouth and nose is a time-honored way to
keep dust and other particles out of the respiratory system. Bandanas provide
some protection against droplets and cough- or sneeze-related spray. Without any kind of nose or
mouth covering, droplets can spray more than 8 feet. Wearing a bandana can
decrease that to about 4 feet.
Cloth masks
with filter:
Some store-bought masks come with filter pockets. You can also make cloth masks
with a pocket for a filter. You can use folded facial tissues as a filter. Simply
slip the folded tissue into the filter pocket. Change the tissue filter daily. Use
a filter of polypropylene material, a durable synthetic fabric often used in
upholstery that can hold an electrostatic charge (which helps it trap small
particles). Adding a polypropylene filter to a two-layer cloth mask can
increase filtration efficiency from 35% to nearly 70%. Masks with exhalation
valves or vents should not be worn to help prevent the person wearing the mask
from spreading COVID-19 to others. That is because the vent allows
unfiltered air to escape.
Cone-style masks:
Manufactured cone-style face masks are molded masks that fit over the mouth and
nose. Usually, there’s also a strip of metal at the top so the wearer can
secure the mask at the bridge of the nose. Cone-style face masks are less
effective at containing droplets and spray than cloth face masks constructed of
quilting cotton. The cone-style masks are more effective than a bandana.
Disposable
surgical mask:
These flat, thin, paper-like masks are usually white and light blue. Surgical
face masks can filter out about 60% of smaller, inhaled particles. They are
primarily intended to stop droplets, sprays, and splatters. Diligently wearing
surgical masks in public spaces can significantly reduce the spread of
respiratory infection. Surgical masks are not designed to be used more than
once. Ideally, you should dispose of a mask after wearing it.
Homemade
cloth mask:
Single-layer masks may only provide 1% particle filtration. A two-layer cotton
mask filters out about 35% of small particles so they offer personal protection
to the wearer. Cotton face masks can decrease droplet spray from 8 feet to 2 ½
inches, which reduces the amount of potentially virus-containing particles you
release into the air.
The effectiveness of
a homemade cloth face mask largely depends upon its construction. Densely woven
cotton fabrics such as quilting cotton are best. Single-layer fabric masks are
less effective than double-layer masks, which may be less effective than
triple-layer masks.
N95, KN95 and other respirators: N95 face respirators offer the most protection against COVID-19 and other respiratory diseases. N95s protect the person wearing the mask because they filter out 95% of particles from the air breathed in. Wearing any of the other masks in this list (cotton and disposable) are intended to protect others around you from your own respiratory droplets and spray.
Cloth and disposable masks also filter particles at varying efficiencies so they offer personal protection as well. KN95 respirators are made to China specifications and standards and N95s are made to U.S. design standards. Both are rated to filter out 95% of very small particles. Buy KN95s that meet the National Institute of Occupational Safety and Health (NIOSH) requirements.
About 60% of KN95s in the
U.S. may be fake and do not meet NIOSH requirements, according to the CDC. Even
more effective than N95 respirators are the N99 (99% filtration), N100 (99.97%
filtration), R95 (95% filtration, and partially resistant to oil), and P95, P99
and P100 (95%, 99% and 99.97% filtration, respectively, and strongly oil
resistant).
Neck gaiters
and balaclavas:
Outdoors enthusiasts often have neck gaiters (essentially, a tube of fabric
that’s worn around the neck and can be pulled up or down, as needed, to protect
the face and neck) or balaclavas (tight-fitting garments that cover the head
and neck) on hand. These can be used as mouth and nose coverings and may
provide some protection against spread of COVID-19.
Many gaiters are made
of synthetic fabric, and synthetic fabric doesn’t seem to be as effective in
preventing the spread of small particles as natural fibers, such as cotton. Neck
gaiters made of synthetic fleece may do more harm than good because they
essentially convert into a fine spray the wearer's respiratory droplets.
Store-bought cloth mask: The effectiveness of a store-bought cloth mask will
depend on its construction. You should look for a mask with at least three
layers of fabric ideally. You want a mask constructed from tight-weave 100%
cotton cloth. A typical cloth face mask is probably at least 50 percent
protective while a high quality masks could be 80-95 percent protective, and
even low-quality masks made of very thin materials could still be 10-20 percent
protective.
T-shirt mask:
Numerous online tutorials show how to craft a face mask from an old T-shirt.
T-shirt masks are cheap and easy to make, but they’re not the most effective. T-shirt
masks are one-third as effective as disposable surgical masks. The upside of
T-shirt masks is that they’re comfortable. The slightly stretchy material
conforms to the face. You may be able to increase the effectiveness of a T-shirt
mask by using more than one layer of material.
“Sometimes, it’s not the people who change. It’s the mask that falls
off.” (QuotesGram)[i]
[i] Adapted from:
· "9 Types of Masks and How Effective
They Are” by Jennifer L.W. Fink
· "Coronavirus Face Masks: What You
Should Know” by WebMD
No comments:
Post a Comment