Question: Should I wear a face mask to help prevent the spread of COVID-19?

Answer passage (source: UK):
page_title: Shops and branches
section_headers: 6. Personal protective equipment (PPE) and face coverings
6.1 Face coverings
section_content: There are some circumstances when wearing a face covering may be marginally
beneficial as a precautionary measure. The evidence suggests that wearing a
face covering does not protect you, but it may protect others if you are
infected but have not developed symptoms.
A face covering can be very simple and may be worn in enclosed spaces where
social distancing isn’t possible. It just needs to cover your mouth and nose.
It is not the same as a face mask, such as the surgical masks or respirators
used by health and care workers. Similarly, face coverings are not the same as
the PPE used to manage risks like dust and spray in an industrial context.
Supplies of PPE, including face masks, must continue to be reserved for those
who need them to protect against risks in their workplace, such as health and
care workers, and those in industrial settings like those exposed to dust
hazards.
It is important to know that the evidence of the benefit of using a face
covering to protect others is weak and the effect is likely to be small,
therefore face coverings are not a replacement for the other ways of managing
risk, including minimising time spent in contact, using fixed teams and
partnering for close-up work, and increasing hand and surface washing. These
other measures remain the best ways of managing risk in the workplace and
government would therefore not expect to see employers relying on face
coverings as risk management for the purpose of their health and safety
assessments.
Wearing a face covering is optional and is not required by law, including in
the workplace. If you choose to wear one, it is important to use face
coverings properly and wash your hands before putting them on and taking them
off.
Employers should support their workers in using face coverings safely if they
choose to wear one. This means telling workers:

wash your hands thoroughly with soap and water for 20 seconds or use hand sanitiser before putting a face covering on, and after removing it
when wearing a face covering, avoid touching your face or face covering, as you could contaminate them with germs from your hands
change your face covering if it becomes damp or if you’ve touched it
continue to wash your hands regularly
change and wash your face covering daily
if the material is washable, wash in line with manufacturer’s instructions. If it’s not washable, dispose of it carefully in your usual waste
practise social distancing wherever possible

You can make face-coverings at home. Find guidance on how to wear and make a
face-covering on GOV.UK.
*[PPE]: Personal protective equipment

Reviewer feedback on this answer:
This provides additional information about how to be safe at pandemic period. It answers directly to the question.
The question is about facemasks.  There is a lot of information here.  It specifically advises to wear facemasks.
This answers the question direct and provides multiple links and guidance to ensure safety

Reviewer ratings:
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