| Soil type | Global standard (theory) | Local practice factor (if no load test) | GEOSS recommendation | |-----------|--------------------------|------------------------------------------|----------------------| | Silty clay (stiff) | 60–100 kPa | 0.7 (local over-excavation common) | Use 50 kPa unless tested | | Loose sand | 30–50 kPa | 0.6 (vibration loosens during boring) | Use 25 kPa | | Weathered shale | 150–200 kPa | 1.0 (if cleaned base) | Test mandatory |