Copyright © Excavations, Subpart P

Copyright © Introduction to Excavation Safety Excavating is one of the most hazardous construction operations for construction workers. According to OSHA, an excavation is a man-made cut, cavity, trench, or depression formed by earth removal. –A trench is a narrow excavation. The depth is greater than the width, but not wider than 15 feet. Nearly all accidents take place in trenches 5 to 15 feet deep and there is usually no warning before a cave-in occurs.

Copyright © Excavation Risks Of the many risks associated with excavations, cave-ins are the greatest. Other hazardous risks include: –Asphyxiation due to lack of oxygen –Inhalation of toxic materials –Fire –Collapse of an excavation due to moving machinery near the edge –Accidental severing of underground utility lines –Cave-ins –Materials and equipment –Vehicles –Spoils –Water accumulation –Oxygen deficiency and toxic fumes –Access/Egress –Falls

Copyright © Competent Workers In order for a worker to be considered competent, they must have specific training in and be knowledgeable about: –Soils classification –The use of protective systems –The requirements of the OSHA excavation standard –Must be capable of identifying hazards, and authorized to immediately eliminate hazards A competent person is responsible for making daily inspections of excavations, including the surrounding areas and protective systems: –Before work starts and as needed –After rainstorms, high winds, or other occurrence which may increase hazards –When one can reasonably anticipate an employee will be exposed to hazards

Copyright © Protecting Employees from Cave-ins Employees should be protected from cave-ins by using adequately designed protection systems. –Protective systems must be able to resist all expected loads to the system. Protective System - A method of protecting employees from cave-ins, material that could fall or roll from an excavation face or into an excavation, or from the collapse of adjacent structures. This includes support systems, sloping and benching systems, and shield systems.

Copyright © Protecting Employees from Cave-ins There are several designs used to protect employees from risks such as cave-ins. They are: –Slopes and configurations of sloping and benching systems –Support systems, shield systems, and other protective systems Each employee in an excavation shall be protected from cave-ins by an adequate protective system except when: –Excavations are made entirely out of stable rock OR –Excavations are less then five feet in depth and examination of the ground by a competent person provides no indication of a potential cave-in

Copyright © Competent Workers Before beginning an excavation, a competent person is responsible for: –Evaluating soil conditions –Constructing protective systems –Testing for low oxygen, hazardous fumes, and toxic gases –Providing safe access and egress –Contacting utilities –Determining the safety equipment needed