| Excavations - Specific Excavation Requirements | OSHA 29 CFR 1926.651 Specific Excavation Requirements |
| Excavations - Requirements for Protective Systems | OSHA 29 CFR 1926.652 Requirements for Protective Systems |
| Confined Space | OSHA 29 CFR 1910.146 Permit Required Confined Space |
| Excavation | EU DIRECTIVE 92/57/EEC Annex IV, part B, section II, 8 - 10 |