Air filters used for clean rooms are classified into 3 basic classes according to EN 779 and EN 1822 standards
1. Pre-filter: divided from G1-G4 filter level:
1.1. G1: Am 65%, capable of filtering 65% of raw dust particles according to EN 779
1.2. G2: 65 ≤ Am <80%
1.3. G3: 80 ≤ Am <90%
1.4. G4: 90 ≤ Am
2. Fine filter (fine filter): divided from the filter level F5-F9
2.1. F5: 40 ≤ Em 60% has the ability to filter 40-60% dust particles according to EN1822 standards (with dust spectrum from 1-10µm)
2.2. F6: 60 ≤ Em <80%
2.3. F7: 80 ≤ Em <85%
2.4. F8: 90 ≤ Em <95%
3. HEPA and ULPA filters: divided from H10-H14 and U15-U17
3.1. H10: Em ≥ 95% is capable of filtering 95% dust particles according to EN1822 standards (with dust particles 0.3µm)
3.2. H11: You are ≥ 98%
3.3. H12: You are ≥ 99.97%
3.4. H13: You are ≥ 99,99%
3.5. H14: You are ≥ 99.999%
3.6. U15: Em ≥ 99.9995% is capable of filtering 99.9995% dust particles according to EN1822 standards (working with dust particles 0.12µm)
3.7. U16: You are ≥ 99.99995%
3.8. U17: You are ≥ 99.999995%
