D | Desktop utility records search | QL-D | - | Undefined | Undefined | - |
|
C | Site reconnaissance | QL-C | - | Undefined | Undefined | Location of underground utilities in relation to above-ground objects. |
|
| | QL-B4 | No | Undefined | Undefined | A presumably existing object – it has not been detected despite the existing information. |
|
B | Detection3 | QL-B3 | No | ± 0.5 m | Undefined | Horizontal position of the object detected using one of the applied geophysical techniques. |
| | QL-B3P | Yes | | | |
|
| | QL-B2 | No | ± 0.25 m or ± 40% of detected depth | ±40% of ± detected depth | Horizontal and vertical positions of the object detected using one of the applied geophysical techniques.4 |
| | QL-B2P | Yes | | | |
|
| | QL-B1 | No | ± 0.15 m or ± 15% of detected depth | ± 15% of detected depth | Horizontal and vertical positions of the object detected by several applied geophysical techniques.5 |
| | QL-B1P | Yes | | | |
A | Verification | QL-A | - | ± 0.05 m | ± 0.025 m | Horizontal and vertical positions of the upper and/or lower part of underground utilities. |