DIN EN 1822-2:1998 High efficiency particulate air filters (HEPA and ULPA) — Part 2: Aerosol production, measuring equipment, particle counting statistics
2011DIN EN 1822-2:2011 High efficiency air filters (EPA, HEPA and ULPA) - Part 2: Aerosol production, measuring equipment, particle counting statistics; German version EN 1822-2:2009
1998DIN EN 1822-2:1998 High efficiency particulate air filters (HEPA and ULPA) — Part 2: Aerosol production, measuring equipment, particle counting statistics