The quality of the processed data in each SPD record is given in the SPD quality flag field `PxxSFLAG' where `xx' identifies the detectors as follows C1, C2, P1, P2, P3 SS, and SL. Table 7.3 gives the coding of each bit in the (8 bit) flag.
| Bit | Description |
| 0 | nominal |
| 1 | calibration measurement saturated |
| 2 | part of plateau data affected by drift |
| 3 | all ramps on plateau rejected |
| 4 | plateau data affected by residual drift |
| 5 | zero standard deviation |
| 6 | empty |
| 7 | zero signal for plateau |