FFP stands for “filtering face piece”. The FFP protection classes are a system to classify the filter capacity of face masks and are determined according to the European EN 149 standard using a NaCl test aerosol with an average particle diameter of 0.6 µm. Classification is done on the basis of the total inward leakage, i.e. face seal leakage, filter penetration, and exhalation valve leakage, if applicable.
- FFP1 masks: total inward leakage may amount to a maximum of 25 %.
- FFP2 masks: total inward leakage may amount to a maximum of 11 %.
- FFP3 masks: total inward leakage may amount to a maximum of 5 %.
