I need to dig a 10' deep trench for a large storm water pipe installation. Do I need a trench box?

In Maryland, OSHA regulations require that all employees in an excavation be protected from cave-ins by an adequate protective system [1]. This typically includes using a trench box (also known as a trench shield), shoring, or sloping the sides of the excavation [2].

For a trench that is 10 feet deep, a protective system is required unless the excavation is made entirely in stable rock, or the excavation is less than 5 feet in depth and a competent person has examined the ground and found no indication of a potential cave-in [1].

Since your trench will be 10 feet deep, you will likely need a protective system. A trench box (shield) is one option [2]. Other options include sloping or shoring the sides of the excavation [2].

Before starting any excavation, you must also identify and locate any underground utilities in the area [3]. Contact utility companies to determine the location of underground installations prior to the start of excavation [3].

Daily inspections of the excavation, adjacent areas, and protective systems must be conducted by a competent person for any evidence of potential cave-ins, failure of protective systems, hazardous atmospheres, or other hazardous conditions [1].