| Particle Size | Examples | Filter Class | Typical Applications |
| Coarse dust, particle size > 10 μm | insects textile fibres and hairs sand fly ash spores, pollen cement dust | G1 G2 | simple applications (e.g. insect screens for compact machinery) |
| G3 G4 | pre-filters and circulation filters for civil defense shelters exhaust filters for spray painting booths, kitchens, etc. inlet air filters for air conditioners and compact machines (e.g. window air conditioners, ventilators) pre-filters for Filter Classes M6 to F8 | ||
| Fine dust, particle size 1-10 μm | pollen spores cement dust fly ash bacteria and germs on host particles | M5 | outside-air inlet filters for rooms with low purity requirements (e.g. factories, warehouse facilities, garages) |
| M5 M6 F7 | pre-filters and circulation filters in central ventilation stations final filters for air conditioning of sales rooms, department stores, offices and certain production plants pre-filters for Filter Classes F9 to E11 | ||
| oil fumes and agglomerated soot tobacco smoke metallic-oxide smoke | F7 F8 F9 | final filters for air conditioning of offices, production plants, control centres, hospitals, EDP centres pre-filters for filter classes E11 to H13 and activated carbon | |
| Suspended particulates, particle size < 1 μm | germs, bacteria, viruses tobacco smoke metallic-oxide smoke | E10 E11 E12 | final filters for rooms with high and highest purity requirements (e.g. for laboratories, for foods processing, pharmaceutical, fine mechanical, optical or electronics plants or medical facilities) |
| E11 | final filters for clean rooms, Classes 100,000 or 10,000 | ||
| oil fumes and soot in nascent state radioactive suspended particulates | E12 H13 | final filters for clean rooms, Classes 10,000 or 100 final filters in civil defense shelters exhaust air filters in nuclear plants | |
| aerosols | H14 U15 U16 | final filters for clean rooms, Classes 10 or 1 |
