Excavating is one of the most hazardous jobs in the construction
industry. Most excavation accidents are the result of cave-ins or collapsing
excavation walls. There are, however, a number of procedures and protective
systems designed to protect workers in or around an excavation.
1. Prior to excavation, the location of underground installations
(e.g., sewer, telephone, electrical, fuel, natural gas, water and other
lines, and underground tanks) must be identified and marked out. New
Jersey One Call (1-800-272-1000) must be called three (3) full working
days before the excavation is planned to begin (see Section
4.0 for
additional information).
2. A daily inspection of the excavation, adjacent areas, and protective
systems by a competent person is required. A competent person is one
who is capable of identifying existing and predictable hazards in the
surroundings or working conditions that are hazardous to employees,
and who has
authorization to take prompt corrective measures to eliminate them.
3. Workers must be protected from cave-ins by an adequate protective
system, except when excavations are made entirely in stable rock or
when the excavations are less than five feet in depth and examination
of the soil by a competent person provides no indication of a potential
cave-in.
4. When used, sloping of the excavation walls must be adequate for
the type of soil. A competent person must determine soil type.
5. Trench boxes or shields must be used in accordance with the
manufacturer’s
recommendations, or as designed and approved by a registered professional
engineer.
6. Ramps, runways, ladders, or stairs used as access must be within
25 feet of a work area if the trench is greater than four feet deep.
7. Any material or equipment that could fall or roll into an excavation
must be placed at least two (2) feet from the edge of the excavation.
All surface encumbrances that may create a hazard to workers must be
removed or supported.
8. A registered professional engineer must design excavations that
are more than twenty feet deep.
9. A warning system for pedestrian and vehicular traffic must be
in place around all excavations. The warning system must consist of
barricades, hand or mechanical signals, or stop logs and flashing lights
at night.
10. Adequate protection from hazards associated with water accumulation
must be in place before working in excavations.
11. Employees exposed to public vehicular traffic must be provided
with and wear reflectorized warning vests.
12. Where workers or equipment are expected to cross over an excavation,
walkways with standard guardrails must be provided.
