prEN 1822-1

This document is applicable to efficient particulate air filters (EPA), high efficiency particulate air filters (HEPA) and ultra-low penetration air filters (ULPA) used in the field of ventilation and air conditioning and for technical processes, e.g. for applications in clean room technology or pharmaceutical industry.
This document establishes a procedure for the determination of the efficiency on the basis of a particle counting method using a liquid (or alternatively a solid) test aerosol and allows a standardized classification of these filters in terms of their efficiency, both local and integral efficiency.
This document is based on particle counting methods which actually cover most needs of different applications.