Excavations

OSHA requires that all excavations in which employees could potentially be exposed to cave-ins be protected by one or more of the following three methods:

Sloping, benching, shoring, and shielding.

The formula for all simple slope excavations 20 feet (6.11 meters) or less deep states that for every foot of depth, the trench must be excavated back:

1 and 1/2 feet.

OSHA defines a trench as:

A narrow excavation made below the surface of the ground in which the depth is greater than the width - with the width not to exceed 15 feet.

Trench boxes or shields must be designed or approved by:

A registered professional engineer.

OSHA defines an excavation as:

Any man-made cavity, depression, trench, or cut in the earth's surface formed by earth removal.

As mentioned in this module, in addition to cave-ins and related hazards, workers involved in excavation work are also exposed to hazards involving:

Falls, falling loads, and mobile equipment.

There is usually some form of warning before a cave-in. (T/F)

False

Shoring or shielding is most often used when:

The location or the depth of the excavation makes sloping back to the maximum allowable slope impractical.

Employees are prohibited from working above other employees on the face of a sloped or benched excavation unless:

The workers on the lower level have overhead protection from falling objects.

To prevent surface water from entering an excavation and to provide adequate drainage of the adjacent area, OSHA standards require the use of:

Water removal equipment, diversion ditches, dikes, or other suitable methods.