24 fully-automatic face mask manufacturing machines（机器 jīqì）that can produce 3 million masks each day will be put into use at the end of March. Using digital technology（科技 kējì）of J-20 fighter jet, Chinese aviation technicians spend 16 days designing the tool that can operate 24 hours a day. #COVID19 #中国加油 | Learn Chinese

Which is the best mask for air pollution? Out of all the masks we commonly wear (cloth mask, surgical mask, N95 and N99) here’s what I found: Cloth masks and surgical masks are ineffective against air pollution. Wearing them feels safe but gives a false sense of protection. N95 is the best option for daily use. It balances filtration and breathability. This is the mask you should be wearing on polluted days. N99 is technically better, but only for very specific use cases like construction sites