Trenching & Excavation
Safety
This page covers the following topics:
- Overview
- Cave-In Prevention Measures
- Support System Installation & Removal Safety
- Providing Protective System Materials & Equipment
- Protection from Fall Hazards
- Additional Information
Overview
According to the Occupational Safety and Health
Administration (OSHA), excavation and trenching are among the most hazardous
construction operations. Hazards involving falling loads, mobile
equipment, and cave-ins can result in worker injury and even fatalities.
To protect workers from these hazards, OSHA requires
employers to use protective systems and provide protection from cave-ins by
requiring employers to:
- Slope and bench the sides of the excavation;
- Support the sides of the excavation; or
- Place a shield between the side of the
excavation and the work area.
Various methods and approaches can be used by an employer to
provide this required protection.
Examples of protective systems include:
- Sloping
the sides of the excavation to an angle not steeper than 1½:1 (for every
foot of depth, the trench must be excavated back 1½ feet). A slope of this
gradation is safe for any type
of soil.
- Designing a sloping
and benching system in accord with tabulated data, such as tables and
charts, approved by a registered professional engineer. This data must be in
writing and must include enough explanatory information (including the criteria
for selecting a system and the limits on the use of the data) for the user to
be able to select an appropriate
protective system.
- Using a trench
box or shield approved by a registered professional engineer or designed in
accord with tabulated data approved by a registered professional engineer.
OSHA also requires that employers take additional
precautions to ensure that:
- Workers are protected from cave-ins.
- Workers are able to safely install and remove
protective systems.
- Workers are given proper materials and equipment
for protective systems.
- Exposure to hazards involving falling loads and
mobile equipment are minimized.
Cave-In Prevention Measures