4 ms·
mask != respirator: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4868605/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4868605/
by everybodyknows 7y ago
mask != respirator:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4868605/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4868605/