SPECIALIST PRACTICE EXAM WITH
CORRECT ACTUAL QUESTIONS AND
CORRECTLY WELL DEFINED ANSWERS
LATEST ALREADY GRADED A+
1. What is the primary hazard in trenching operations?
A. Noise exposure
✔ B. Cave-ins
C. Heat stress
D. Electrical shock
Answer: B. Cave-ins
Explanation: Cave-ins are the most dangerous and deadly
hazard in trenching work. Soil can collapse suddenly,
crushing or burying workers within seconds.
2. At what depth is protective systems generally required?
,A. 3 feet
✔ B. 5 feet
C. 10 feet
D. 15 feet
Answer: B. 5 feet
Explanation: OSHA requires protective systems (sloping,
shoring, shielding) for trenches 5 feet or deeper unless the
excavation is made entirely in stable rock.
3. Which soil type is the most stable?
✔ A. Type A soil
B. Type B soil
C. Type C soil
D. Loose fill
Answer: A. Type A soil
Explanation: Type A soil is cohesive and least likely to
collapse. Type C is the least stable.
,4. Which soil is the least stable?
A. Type A
B. Type B
✔ C. Type C
D. Clay
Answer: C. Type C soil
Explanation: Type C soil is granular and unstable, such as
sand or gravel, making it highly prone to collapse.
5. What is a protective system used in trenching?
A. PPE
✔ B. Trench box
C. Barricade tape
D. Warning signs
Answer: B. Trench box
, Explanation: Trench boxes protect workers from cave-ins by
shielding them inside reinforced structures.
6. Who is responsible for ensuring trench safety
compliance?
A. Workers only
B. Equipment operator
✔ C. Competent person
D. Client
Answer: C. Competent person
Explanation: A competent person is trained to identify
hazards and has authority to correct unsafe conditions.
7. What is the maximum allowable slope for Type C soil?
A. 1:1
✔ B. 1.5:1
C. 2:1
D. 3:1