A trench is defined as a narrow excavation (in relation to its length) made below the surface of the ground. In general, the depth of a trench is greater than its width, but the width of a trench (measured at the bottom) is not greater than 15 feet. Trench excavation protection is used for the installation of linear drainage or electrical features that will result in trenches deeper than 5 ft. It provides vertical or sloped cuts, benches, shields, support systems, or other systems providing the necessary protection in accordance with

OSHA Standards and Interpretations, 29 CFR 1926, Subpart P, Excavations

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