When benching, the maximum depth of excavation is how many feet?

• A. 20 ft
• B. 10 ft
• C. 30 ft
• D. 25 ft

Answer: (A)

Benching protects workers by cutting the trench wall into stepped levels, reducing the amount of earth that can slide at any one point. This method works for shallower digs, but its stability becomes harder to maintain as depth increases. In standard practice, the maximum depth you can safely achieve with benching is 20 feet. If the trench needs to go deeper, a different protective system (such as shoring or shielding) designed for the soil and conditions is required. The exact allowable depth can vary with soil type, moisture, and loads, but 20 feet is the common limit for benching.