Industrial environments are not always as safe as they should be. Heavy industries like construction…
California construction and utility workers who are required to work in trenches and excavations are 112 percent more likely to die in a work-related accident than general construction workers. This is according to EHS Today, the occupational safety and health magazine.
Trenches are full of potential safety and environmental hazards. Workers face a substantial risk of asphyxiation from lack of oxygen, inhalation of toxic fumes, or drowning in a confined space. Since the weight of one cubic yard of earth is equivalent to that of a car, cave-ins are a particular hazard.
The Occupational Safety and Health Administration defines an excavation as earth removal resulting in a cut, cavity or depression in the surface of the earth. A trench is a deep, narrow underground excavation up to 15 feet wide
In addition to cave-in dangers, other trench and excavation hazards include a person and/or load of soil or other debris falling into it; adverse atmospheric conditions; and mobile equipment malfunction or mishandling. OSHA warns workers never to enter an unprotected trench. Any trench deeper than 5 feet requires an installed protective system unless it is cut into completely stable rock. The protective system of any trench 20 feet deep or deeper must have been designed or approved by a registered professional engineer.
There are three different types of protective systems as follows:
1. Sloping – Trench walls are cut at an angle that slopes away from the excavation.
2. Shoring – Trench walls are braced with aluminum hydraulic or other kinds of supports.
3. Shielding – Trench boxes or other kinds of supports shield workers from soil cave-ins.
OSHA cautions workers to inspect all trenches at the beginning of each work shift and/or after a rainfall. In addition, they need to keep their heavy equipment back from trench edges, never work under a raised load, and be aware of the location of underground utilities.