One common concern about cloth face masks is the level of filtration they provide. The fabric’s mesh is often too open to filter out smaller particles such as smoke, dust, or viruses. A popular ...

Melitta, the German maker of the original paper coffee filter, retooled its production to make masks. A director called the filter’s perfect fit over the face “a gift from heaven.” Credit...Daniel ...

Which filter inserts for masks are best? Cloth masks typically are the most affordable options for staying healthy and safe in crowded public settings because you can wash them and repeatedly wear ...

BERLIN — As the wave of coronavirus infections broke over Europe in March, causing reserves of medical supplies to disappear, German authorities made a nationwide appeal: More safety masks were ...