Scientists tested 14 types of masks — here are the ones that worked and didn’t

Bandannas, gaiters and knitted masks are some of the least effective face coverings for preventing the spread of coronavirus, according to a new study.

Researchers at Duke University made the discovery while testing 14 different types of masks, according to the study published Friday.

N95 masks, often used by health care professionals, worked best to stop the transmission of respiratory droplets during regular speech. Other good performers at stopping leakage were three-layer surgical masks and cotton masks, which can be made at home, the researchers with Duke’s physics department found.