| Light ions | Cylindrical chambers | Plane-parallel chambers | ||
| Component | Light ions | 60Co + light ions | Light ions | 60Co + light ions |
| sw,air | 2.0 | 2.1 | 2.0 | 2.1 |
| Wair/e | 1.5 | 1.5 | 1.5 | 1.5 |
| pQ (combined) | 1.0 | 1.0 | 1.0 | 1.8 |
| Total uncertainty in kQ,Qo | - | 2.8 | - | 3.2 |