5.2 “United States” American NIOSH standard [15] Filter material for masksThe quality and filtration efficiency are graded, and the standard is recognized all over the world Degree is the highest. According to…Mar 20, 2021Mar 20, 2021
5.1.3 YY/T0969–13[12] This standard is a one-time useThe industry standard for medical masks was released in 2013–10–21, 2014 -10–01 implementation. Ordinary medical masks meet this standard…Mar 20, 2021Mar 20, 2021
