| Quality | FSR | Digital CR |
| 1) Good | 1735 (61.9) | 2032 (72.5) |
| 2) Acceptable, no defects | 701 (25.0) | 621 (22.2) |
| 3) Acceptable, some defects | 335 (12.0) | 129 (4.6) |
| 4) Unacceptable | 13 (0.46) | 0 |
| 5) Did not rank quality# | 18 (0.64) | 20 (0.71) |
Data are presented as n (%). Includes initial 1,401 miner participants. Image quality assessed by two B readers for film-screen radiography (FSR) and digital storage phosphor computed radiography (CR) images. The 13 unacceptable quality images were from 13 miners and all images obtained from those miners were excluded from subsequent analyses. #: data for other fields, including small opacity profusion characterisations, were complete.