I have seen many youtube videos from non-English speaking countries (mostly in Asia) that show how to make a home-made face shield, to prevent COVID transmission. They seem to be much used by health care workers.
Why are they not more used in the West, e.g. United States? I'm asking about (a) health care workers, (b) vulnerable populations, and (c) the general population.
A face shield can be made out of a transparent report cover and materials commonly available at home, and doesn't add to the discomfort of breathing, since air flows to the face through the side and bottom edges.
It can be combined with a mask that covers the nose and mouth.