Masks being used by thousands of SA health workers to protect them from Covid-19 infection have failed safety tests.

None of the 12 brands of KN95 masks tested at the University of Cape Town offers the protection provided by the “gold standard” N95 mask, according to the results of a study published on Wednesday in the SA Medical Journal (http://www.samj.org.za/index.php/samj/article/view/13162/9621)...