Historical
BS EN 1822-4:2000
High efficiency air filters (HEPA and ULPA). Determining leakage of filter element (scan method) (British Standard)
This standard applies to high efficiency air filters and ultra low penetration air filters (HEPA- and ULPA-filters) used in the field of ventilation and air conditionning and for technical processes, for example, for clean room technology or applications in the nuclear or pharmaceutical industry. It establisches a procedure for the determination of the efficiency on the basis of a particle counting method using a liquid test aerosol, and allows a standardized classification of these filters in terms of their efficiency.
British Standards Institution [bsi]