CO Excavation Contractor Exam Questions
and Correct Answers (Verified Answers)
Plus Rationale 2027 Q&A| Instant
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1. What is the primary hazard associated with trenching and
excavation operations?
A. Noise exposure
B. Electrical shock
C. Cave-ins
D. Heat stress
Rationale: Cave-ins are the leading life-threatening hazard in
excavation work. Proper sloping, benching, shoring, or shielding is
used to protect workers from collapsing soil.
2. Under OSHA definitions, an excavation is best described as:
A. Only a trench deeper than 5 feet
B. A temporary foundation hole
,C. Any man-made cut, cavity, trench, or depression in an earth surface
formed by earth removal
D. Any hole containing underground utilities
Rationale: OSHA defines an excavation broadly as a man-made cut,
cavity, trench, or depression formed by removing earth. Trenches are
included within this definition.
3. Under OSHA's definition, a trench is generally a narrow excavation
whose depth is greater than its width and whose bottom width
does not exceed:
A. 10 feet
B. 12 feet
C. 15 feet
D. 20 feet
Rationale: OSHA generally defines a trench as a narrow excavation in
which the depth is greater than the width and the bottom width is not
greater than 15 feet.
4. Which OSHA subpart specifically addresses excavation and
trenching requirements?
A. Subpart L
B. Subpart O
,C. Subpart P
D. Subpart R
Rationale: OSHA's excavation requirements are contained in 29 CFR
Part 1926, Subpart P. The subpart includes requirements for
excavation operations, protective systems, and soil classification.
5. Which of the following is an acceptable method of protecting
workers from cave-ins?
A. Increasing equipment speed
B. Removing all warning signs
C. Sloping the excavation walls
D. Placing spoil piles directly against the trench wall
Rationale: OSHA recognizes sloping, benching, shoring, and shielding
as protective approaches for excavation hazards. The appropriate
method depends on site and soil conditions.
6. A trench is 6 feet deep. Which statement is generally correct
regarding worker protection?
A. No protective system is ever required
B. Only a warning sign is required
C. A protective system is generally required unless an applicable
, exception applies
D. Workers may enter without inspection
Rationale: Trenches 5 feet or deeper generally require a protective
system unless the excavation is made entirely in stable rock. For
excavations less than 5 feet deep, a competent person may determine
that protection is unnecessary based on the conditions.
7. Who must inspect an excavation for hazardous conditions before
employees enter?
A. Any available laborer
B. The equipment operator only
C. A competent person
D. The property owner
Rationale: OSHA requires inspections by a competent person. The
competent person must be capable of identifying existing and
predictable hazards and must have authority to take prompt
corrective action.
8. When should an excavation be inspected after a significant
rainstorm?
A. Only at the end of the project
B. Only if an employee requests an inspection
and Correct Answers (Verified Answers)
Plus Rationale 2027 Q&A| Instant
Download Pdf
1. What is the primary hazard associated with trenching and
excavation operations?
A. Noise exposure
B. Electrical shock
C. Cave-ins
D. Heat stress
Rationale: Cave-ins are the leading life-threatening hazard in
excavation work. Proper sloping, benching, shoring, or shielding is
used to protect workers from collapsing soil.
2. Under OSHA definitions, an excavation is best described as:
A. Only a trench deeper than 5 feet
B. A temporary foundation hole
,C. Any man-made cut, cavity, trench, or depression in an earth surface
formed by earth removal
D. Any hole containing underground utilities
Rationale: OSHA defines an excavation broadly as a man-made cut,
cavity, trench, or depression formed by removing earth. Trenches are
included within this definition.
3. Under OSHA's definition, a trench is generally a narrow excavation
whose depth is greater than its width and whose bottom width
does not exceed:
A. 10 feet
B. 12 feet
C. 15 feet
D. 20 feet
Rationale: OSHA generally defines a trench as a narrow excavation in
which the depth is greater than the width and the bottom width is not
greater than 15 feet.
4. Which OSHA subpart specifically addresses excavation and
trenching requirements?
A. Subpart L
B. Subpart O
,C. Subpart P
D. Subpart R
Rationale: OSHA's excavation requirements are contained in 29 CFR
Part 1926, Subpart P. The subpart includes requirements for
excavation operations, protective systems, and soil classification.
5. Which of the following is an acceptable method of protecting
workers from cave-ins?
A. Increasing equipment speed
B. Removing all warning signs
C. Sloping the excavation walls
D. Placing spoil piles directly against the trench wall
Rationale: OSHA recognizes sloping, benching, shoring, and shielding
as protective approaches for excavation hazards. The appropriate
method depends on site and soil conditions.
6. A trench is 6 feet deep. Which statement is generally correct
regarding worker protection?
A. No protective system is ever required
B. Only a warning sign is required
C. A protective system is generally required unless an applicable
, exception applies
D. Workers may enter without inspection
Rationale: Trenches 5 feet or deeper generally require a protective
system unless the excavation is made entirely in stable rock. For
excavations less than 5 feet deep, a competent person may determine
that protection is unnecessary based on the conditions.
7. Who must inspect an excavation for hazardous conditions before
employees enter?
A. Any available laborer
B. The equipment operator only
C. A competent person
D. The property owner
Rationale: OSHA requires inspections by a competent person. The
competent person must be capable of identifying existing and
predictable hazards and must have authority to take prompt
corrective action.
8. When should an excavation be inspected after a significant
rainstorm?
A. Only at the end of the project
B. Only if an employee requests an inspection
