2011DIN EN 1822-4:2011 High efficiency air filters (EPA, HEPA and ULPA) - Part 4: Determining leakage of filter elements (scan method); German version EN 1822-4:2009
1970DIN EN 1822-4 E:2008-04 High efficiency air filters (EPA, HEPA and ULPA) - Part 4: Determining leakage of filter elements (scan method)
2000DIN EN 1822-4:2001 High efficiency particulate air filters (HEPA and ULPA) — Part 4: Determining leakage of filter element (Scan method)