Type of study | QL | Post-processing | Location accuracy | Additional data | ||
---|---|---|---|---|---|---|
Horizontal1 | Vertical2 | |||||
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 | 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 | 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. |
Method | gnD300 | gs90 | eSA1 | eSA2 | eSA3 | eSA4 | 3eSD |
---|---|---|---|---|---|---|---|
GPR-MS50 | 0.15 | 0.21 | 0.17 | 0.17 | 0.11 | 0.13 | 0.12 |
Distance | 0.14 | 0.17 | 0.14 | 0.15 | 0.15 | 0.15 | 0.09 |
GPR-MS50 method | gnD300 | gs90 | eSA | eSA | eSA | eSA | 3eSD |
---|---|---|---|---|---|---|---|
Min | 0.41 | -0.04 | -0.04 | -0.01 | -0.01 | -0.13 | -0.22 |
Max | 0.53 | 0.09 | 0.24 | 0.05 | 0.03 | 0.03 | 0.08 |
Mean | 0.47 | 0.02 | 0.10 | 0.02 | 0.01 | -0.05 | -0.06 |
Distance method1 | gnD300 | gs90 | eSA | eSA | eSA | eSA | 3eSD |
Min | 0.37 | -0.14 | -0.11 | -0.23 | -0.21 | -0.25 | -0.39 |
Max | 0.46 | 0.09 | 0.16 | -0.11 | -0.11 | -0.16 | -0.10 |
Mean | 0.42 | -0.04 | 0.02 | -0.17 | -0.16 | -0.20 | -0.24 |