An engineer must approve any trench shoring design above which depth?

An engineer must approve any trench shoring design above which depth?

• A. 4 feet deep
• B. a water line
• C. 50 feet in length
• D. 20 feet deep

Answer: (D)

In trench safety, the need for an engineer to approve the shoring design appears as the trench becomes deep enough that earth pressures and stability require formal engineering analysis. The threshold here is 20 feet deep, so any trench shoring design above that depth must be approved by a licensed engineer to ensure the protective system will safely withstand the loads. Protective systems are required for trenches 4 feet and deeper, but the design up to 20 feet can often be performed by a competent person on site. The other options don’t relate to the depth at which engineering approval is required: a water line is about utility presence, not design authority; and length (50 feet) isn’t the factor that triggers engineer approval. Therefore, 20 feet deep is the correct depth at which an engineer must approve the trench shoring design.

In trench safety, the need for an engineer to approve the shoring design appears as the trench becomes deep enough that earth pressures and stability require formal engineering analysis. The threshold here is 20 feet deep, so any trench shoring design above that depth must be approved by a licensed engineer to ensure the protective system will safely withstand the loads.

Protective systems are required for trenches 4 feet and deeper, but the design up to 20 feet can often be performed by a competent person on site. The other options don’t relate to the depth at which engineering approval is required: a water line is about utility presence, not design authority; and length (50 feet) isn’t the factor that triggers engineer approval. Therefore, 20 feet deep is the correct depth at which an engineer must approve the trench shoring design.