Home excavation projects can range in size from an entire basement, to a foundation for a garage or addition, to a small utility trench. Excavation may also be needed to create drainage space around your home’s foundation that addresses a basement prone to flooding. Whatever the project, as a homeowner you should know what an excavation is, as well as a few dos and don’ts for excavation projects.
What is an Excavation?
The Occupational Safety and Health Administration (OSHA) defines an excavation as “any man-made cut, cavity, trench, or depression in the Earth’s surface formed by earth removal.” Cave-ins pose the greatest risk to workers and other potential hazards include falls, falling loads, hazardous atmospheres, and incidents involving mobile equipment. Trench collapses cause dozens of fatalities and hundreds of injuries each year.
- Do consult with a civil engineer who will create a Scope of Work to ensure that your project is completed as efficiently and safely as possible.
- Do call 811 before beginning any excavation project. Calling 811 or visiting www.call811.com will provide the contact information for your local or government utility location service or dig line, which is completely free to use. This service will give you the locations of all underground gas, electric, water, sewer and communications pipes and cables in the area. By law you must call Dig Safe Line before beginning any excavation or digging project anywhere in the US.
- Do hire a licensed contractor with the expertise to perform the excavation. Review the contractor’s website, check with the Better Business Bureau and contact the contractor’s references.
- Do make sure that all the necessary permits have been obtained from your city or town’s building department.
- Do be sure that your excavation contractor has written documentation of liability and workers’ compensation insurance for all workers on site.
- Do protect yourself and others at the excavation site. Trenches five feet (1.5 meters) deep or greater require a protective system unless the excavation is made entirely in stable rock. Trenches 20 feet (6.1 meters) deep or greater require that the protective system be designed by a registered professional engineer or be based on tabulated data prepared and/ or approved by a registered professional engineer.
- Do ask your excavation contractor about what safety measures and protective systems have been put in place to prevent cave-ins and other hazards. These could include sloping, shoring or shielding. According to OSHA, sloping involves cutting back the trench wall at an angle inclined away from the excavation. Shoring requires installing aluminum hydraulic or other types of supports to prevent soil movement and cave-ins. Shielding protects workers by using trench boxes or other types of supports to prevent soil cave-ins. Designing a protective system can be complex because many factors must be considered: soil classification, depth of cut, water content of soil, changes due to weather or climate, surcharge loads (eg., spoil, other materials to be used in the trench) and other operations in the vicinity.
- Do have a qualified “competent person” inspect the excavation daily to ensure that excavation hazards have been eliminated. OSHA defines a competent person as “an individual who is capable of identifying existing and predictable hazards or working conditions that are hazardous, unsanitary, or dangerous to employees and who is authorized to take prompt corrective measures to eliminate or control these hazards and conditions.” Excavations and trenches should also be inspected after rainstorms.
- Don’t enter an unprotected trench! Cave-ins can occur in a matter of seconds, and can cause serious or fatal injuries. According to OSHA, trench collapses cause dozens of fatalities and hundreds of injuries each year.
- Don’t allow heavy equipment near the excavation edges. Most protective systems, such as sloping, shoring or shielding, are designed to support the weight of the soil, not the additional weight of heavy equipment. The equipment that is being used to dig the excavation should be placed as far away from the edge as possible and in the area least likely to collapse.
- Don’t allow surcharge such as excess soil, other materials, etc. to be placed within 2 feet of the excavation edges. Not only can excess soil and materials increase the likelihood of an excavation cave-in, but these materials can fall into the excavation as well.
- Do not allow work to occur under raised loads. This is common sense: keep all personnel from working under raised loads, which could fall and cause injury.
New England Enterprises has the equipment and the expertise for your excavation project, large or small. Contact New England Enterprises for an expert consultation.