Different germs can survive on a used mask for different periods of time. Viruses can survive for a
few hours up to a few days on masks. Used single-use masks should be binned immediately after
use. Always wash your hands before wearing and after taking off a mask.
Masks that are not made out of cloth are single use and thus not reusable. They should be
discarded after being used.
Masks should only be considered as a complementary measure to established preventive practices
such as physical distancing, cough and sneeze etiquette, hand hygiene and avoiding touching one’s
face. They are not replacements for these practices.
Visors/Face shields, their use and care
Visors/Face shields are simple, transparent screens that cover the face and help
prevent infectious droplets from entering the eyes, nose and mouth and should
extend to below the chin. They can be worn separately or in conjunction with
masks but are the most effective when worn in conjunction with masks,
blocking splashes and sprays from reaching the face and preventing people
from touching their faces. However, due to their design, they may allow
respiratory droplets to exit or enter through the open gaps between the visor
and the face. Since we do not yet have evidence that face shields are as effective as source control
or protection from respiratory droplets as masks, we recommend that masks should be used in
preference to visors (or in conjunction with them), while the use of visors alone is discouraged.
However in certain situations where a mask is not practical or cannot be tolerated ( e.g. children
with special needs, certain health issues) visors can be used as an alternative to masks.
The advantage of visors/face shields is their durability, allowing them to be worn an indefinite
number of times, the ability to easily clean them after use, their comfort, and that they may also
prevent the wearer from touching their face. Importantly, visors/face shields create a relative cover
for all the portals of entry for the virus: the eyes, the nose, and the mouth. They are available in
various sizes, including for children- but should not be worn by children under 3 years of age.
Visors/face shields typically consist of two main parts: a transparent visor that covers the face and
which is usually made of plastics such as polycarbonate, propionate, acetate, polyvinyl chloride (PVC),
and polyethylene terephthalate glycol (PETG); and a method of holding the visor in place, such as a
headband or strap.
The strap can be made of moulded plastic, 3D-printed plastic or even elastic. Some visors/face shields
are designed to be thrown away after a single use while others can be disinfected and reused.
Although evidence on visors/face shields is limited, what is available suggests that the following face
shields may provide better source control than others:
Face shields that wrap around the sides of the wearer’s face and extend below the chin.
Hooded face shields.
Visors/Face shields that do not cover all the face are not recommended since they do not provide
Visor/Face shield wearers should wash their hands before and after removing the face shield and
avoid touching their eyes, nose and mouth when removing it.
Visors/Face shields should ideally be the reusable type and should be disinfected appropriately at
each use with alcohol wipes or disinfectant wipes or disinfectant spray or germicidal wipes or with
soap and water. They then should be left to dry before the next use.
Disposable visors/ face shields may be used as long as they keep their shape and remain intact.
If your visor/ face shield breaks, it must be replaced.
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