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Trenching and Excavation

Each year over 60 people are killed while working in and around trenches and excavations. Working in an unprotected trench or excavation can lead to death from becoming buried alive. In fact, this task is so hazardous that OSHA has identified it as one of the top four hazards that can cause death to workers. OSHA has also targeted trenching and excavations through a National Emphasis Program (NEP) which, when found, requires a mandatory inspection.
Why is trenching and excavation so deadly?
A cubic yard of dirt weighs nearly 1 and one half tons, or around 3000 pounds. A worker in an unprotected trench can easily become immobile or trapped by sliding dirt around the legs or ankles. When unprotected dirt reaches an employee’s chest area, it quickly be-comes impossible to take a breath. Once trapped by sliding dirt, rescues becomes a touch and go operation; nearly every em-ployee buried by dirt in a trench or excavation dies long before reached by emergency responders.
How can these worker deaths be prevented?
Plan your job – A Competent person has been trained to examine soil types and environmental that can determine what type of equipment and preplanning will be needed. Use information to choose a protection system for the type of hazard – Soil analysis is important in order to determine appropriate sloping, benching, and shoring.
Monitor the work – Your previous training will enable you to recognize the signs and hazards that can lead to collapse.
Recognize some critical signs of danger
Some easily identifiable and recognizable hazards during trenching and excavations include working with heavy machinery; man-ual handling of materials; working in proximity to traffic; electrical hazards from overhead and underground power-lines; and underground utilities, such as natural gas.
Fatal Fact: Two employees were installing storm drain pipes in a trench, approximately 20-30 feet long, 12-13 feet deep and 5-6 feet wide. The side walls consisted of unstable soil undermined by sand and water. There was 3-5 feet of water in the north end of the trench and 5-6 inches of water in the south end. At the time of the accident, a backhoe was being used to clear the trench. The west wall of the trench collapsed, and one employee was crushed and killed. As result of the its investigation, OSHA issued citations for one willful, one serious, and one-other-than-serious violation of its construction standards. OSHA’s construction safety standards include several requirements which, if they had been followed here, might have prevented this fatality.