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Performance of HEPA filter
| Type | Efficiency with sodium flame method under nominal flow rate | Efficiency with sodium flame method under 20 % of nominal flow rate | Resistance under nominal flow rate |
|---|---|---|---|
| % | % | Pa | |
| A | 99.99 > E ≥ 99.9 | No requirement | ≤190 |
| B | 99.999 > E ≥ 99.99 | 99.99 | ≤220 |
| C | E ≥ 99.999 | 99.999 | ≤250 |
