What is the ASTM criteria for a Level 3 medical mask rating?
| CHARACTERISTIC | LEVEL 3 |
|---|---|
| Bacterial filtration efficiency, % | ≥ 98 |
| Sub-micron particulates filtration efficiency at 0.1 micron, % | ≥ 98 |
| Differential pressure, mm H2O/cm2 (Breathability) | < 5.0 |
| Resistance to penetration by synthetic blood, minimum pressure in mm Hg for pass result | 160 |
| Helmke Drum | Category 2 |