![What is the best mask for COVID-19? A mechanical engineer explains the science after 2 years of testing masks in his lab What is the best mask for COVID-19? A mechanical engineer explains the science after 2 years of testing masks in his lab](https://images.theconversation.com/files/442358/original/file-20220124-27-1ch5axg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip)
What is the best mask for COVID-19? A mechanical engineer explains the science after 2 years of testing masks in his lab
![Amazon.com: ALASKA BEAR Sleep Mask for Side Sleepers Best Eye Mask Contoured Cup for All Sleeping Positions Men Women Cool Night Blindfold 100% Light Blackout Cover Comfort Concave Padding, Machine Washable : Amazon.com: ALASKA BEAR Sleep Mask for Side Sleepers Best Eye Mask Contoured Cup for All Sleeping Positions Men Women Cool Night Blindfold 100% Light Blackout Cover Comfort Concave Padding, Machine Washable :](https://m.media-amazon.com/images/I/61eUm+0UvcL.jpg)
Amazon.com: ALASKA BEAR Sleep Mask for Side Sleepers Best Eye Mask Contoured Cup for All Sleeping Positions Men Women Cool Night Blindfold 100% Light Blackout Cover Comfort Concave Padding, Machine Washable :
![Woman Wearing Incorrectly Face Mask Covering Whole Face Including Eyes Side View. Stock Image - Image of prevention, prevent: 206620035 Woman Wearing Incorrectly Face Mask Covering Whole Face Including Eyes Side View. Stock Image - Image of prevention, prevent: 206620035](https://thumbs.dreamstime.com/z/woman-wearing-incorrectly-face-mask-covering-whole-face-including-eyes-side-view-incorrect-wrong-way-wearing-face-mask-206620035.jpg)
Woman Wearing Incorrectly Face Mask Covering Whole Face Including Eyes Side View. Stock Image - Image of prevention, prevent: 206620035
![Side View Of Medical Face Mask Isolated On White Background Stock Photo - Download Image Now - iStock Side View Of Medical Face Mask Isolated On White Background Stock Photo - Download Image Now - iStock](https://media.istockphoto.com/id/1212952102/photo/side-view-of-medical-face-mask-isolated-on-white-background.jpg?s=612x612&w=0&k=20&c=ATcbrPuW1XsZPL7HPoIOk_mIfGrI1s4-Mgt56kdh6cY=)
Side View Of Medical Face Mask Isolated On White Background Stock Photo - Download Image Now - iStock
![4,400+ Surgical Mask Side View Stock Photos, Pictures & Royalty-Free Images - iStock | Surgical mask side view vector 4,400+ Surgical Mask Side View Stock Photos, Pictures & Royalty-Free Images - iStock | Surgical mask side view vector](https://media.istockphoto.com/id/1225003382/photo/one-young-woman-wearing-a-surgical-mask-outdoor.jpg?s=612x612&w=0&k=20&c=C4_E234_vGCSbXGfRkrjC8ZQ7-YNENy5DN9lDqWaC6k=)