Adapted full-face snorkel masks as an alternative for COVID-19 personal protection during aerosol generating procedures in South Africa: A multi-centre, non-blinded in-situ simulat... oleh Ronel Herselman, Vidya Lalloo, Veronica Ueckermann, Daniel J. van Tonder, Edwin de Jager, Sandra Spijkerman, Wanda van der Merwe, Marizane du Pisane, Fanie Hattingh, David Stanton, Ross Hofmeyr