Standards for MASK
| Class[5] | Filter penetration limit (at 95 L/min air flow) | Inward leakage | Typical elastic band |
|---|---|---|---|
| FFP1 | Filters at least 80% of airborne particles | <22% | Yellow |
| FFP2 | Filters at least 94% of airborne particles | <8% | Blue or White |
| FFP3 | Filters at least 99% of airborne particles | <2% | Red |
