In comparison, the scientists said the human hair is about 70 microns in diameter. Among the many types of facemasks in use, such as cloth masks, surgical masks, and N95 masks, they said only the latter can filter out aerosol-sized droplets. The performance of face masks worn for many hours, such as by health care or other essential workers, impact how effective overall mask wearing can be, the researchers added.
They found that face masks made of hybrid polymer materials could filter particles at high efficiency while simultaneously cooling the face since the fibres used in these allow heat to escape from beneath the mask. "There could be some relation between breathing resistance and the flow resistance of the face mask which will need to be studied for a face mask-wearing interval," said Heow Pueh Lee, another co-author of the study.
"Also, the environmental condition in the compartmental space within the face mask will need to be more accurately quantified using miniaturised sensors and the development of human replicas for such studies," Lee said. Based on the analysis, the researchers underscored the importance of consistent use of efficient facemasks, such as surgical masks.
