Excavations Trenching and Shoring

Excavations, Trenching and Shoring

1. The determination of the angle of repose and design of the supporting system shall be based on careful consideration of the following: depth of the cut; anticipated changes in the soil due to air, sun and water; and ground movement caused by vehicle vibration or blasting and earth pressures.

2. Trenches 5 feet and over in depth shall be shored, benched or walls cut back to protect employees from cave-ins.

3. Ladders or other means of egress shall be provided in each excavation. No more than 25 feet of lateral travel shall be required to reach any such ladder.

4. One of four (4) methods of shoring may be used:

a. Timber shoring.

b. Hydraulic shoring, trench jacks, air shores and shields in accordance with the manufacturer's tabulated data.

c. Shoring or shielding methods that are based on tabulated data-tables and charts that have been approved by a registered professional engineer.

d. Any design of protective method so long as it is approved by a registered professional engineer.

5. Each excavation must be inspected daily by a competent person for evidence of possible cave-ins, failure of protective system, hazardous atmosphere or other hazardous conditions.

6. Inspections shall also be made after a rainstorm or other hazard increasing occurrence.

7. In locations where oxygen deficiencies or concentrations of hazardous or explosive gases are possible, the atmosphere in the excavation must be tested by a qualified person prior to start of work and retested at intervals as required by conditions.

8. Trenches and excavations must be protected by barricades or railing where pedestrian or vehicle traffic is likely.