Leak Testing by He-Leakage Test Method (HLT-560, Pfeiffer Vacuum AG, Zürich, Switzerland) on Empty 2 mL Vials Crimped at 40 N (n = 10)
| Cu wire diameter (μm) | Equivalent diameter of a circular-shaped aperture (μm) when applying 30 N capping force | Equivalent diameter of a circular-shaped aperture (μm) when applying 50 N capping force | Number of leaking vials* | Leak rate—order of magnitude (mbar × L/s) |
|---|---|---|---|---|
| 0 | 0 | 0 | 0/10 | <10−8 |
| 15 | 12 | 9 | 0/10 | <10−8 |
| 20 | 16 | 13 | 2/10 | 10−5 |
| 28 | 22 | 18 | 6/10 | 10−4 |
| 40 | 31 | 25 | 10/10 | 10−4 |
| 60 | 47 | 38 | 10/10 | 10−3 |
↵* Acceptance criteria leak rate <1 × 10–7 mbar × L/s (tight system).