Sloping & Benching Definitions

Actual slope refers to the slope to which an excavation face is excavated.

Distress means that the soil is in a condition where a cave-in is about to happen or is likely to occur. Distress is indicated by the development of fissures in the face of or next to an open excavation. Examples include the following:

• The sinking or settling of the edge of an excavation
• The slumping of material from the face of an excavation, or the bulging or heaving of material from the bottom of an excavation
• The spalling of material from the face of an excavation
• The occurrence of ravelling, which means pebbles or little clumps of material suddenly separating from the face of an excavation and trickling or rolling down into the excavation

Maximum allowable slope means the steepest incline of an excavation face that is acceptable for the most favorable site conditions as protection against cave-ins, and is expressed as the ratio of horizontal distance to vertical rise (H:V).

Short-term exposure means a period of time less than or equal to 24 hours that an excavation is open.

To learn more about Trenching and Excavation visit our Trenching and Excavation Safety Online Training web page.