NCCCO Digger Derrick Operator Practice
Exam Questions And Correct Answers
(Verified Answers) Plus Rationales 2026
Q&A Instant Download Pdf
1. What is the primary purpose of a digger derrick?
A. Excavating trenches
B. Lifting and placing poles and materials
C. Compacting soil
D. Transporting personnel
Answer: Lifting and placing poles and materials
Rationale: Digger derricks are designed mainly for lifting loads such as
utility poles and equipment.
2. The load chart on a digger derrick provides information about:
A. Fuel consumption
B. Maximum allowable loads at given radii
C. Operator schedules
D. Maintenance intervals
Answer: Maximum allowable loads at given radii
Rationale: Load charts indicate safe lifting capacities based on boom
angle, length, and radius.
3. What is the center of gravity?
A. The heaviest part of a load
B. The geometric center of a load
, C. The point where weight is evenly distributed
D. The top of the load
Answer: The point where weight is evenly distributed
Rationale: The center of gravity is the balance point where the load’s
weight is evenly distributed.
4. Before operating a digger derrick, the operator must:
A. Call the supervisor
B. Inspect the equipment
C. Refuel the machine
D. Check weather reports only
Answer: Inspect the equipment
Rationale: Pre-operation inspections are required to ensure safe
operation.
5. Outriggers are used to:
A. Lift loads
B. Stabilize the machine
C. Increase speed
D. Reduce fuel consumption
Answer: Stabilize the machine
Rationale: Outriggers provide stability during lifting operations.
6. The working radius is defined as:
A. Distance from boom tip to ground
B. Distance from center of rotation to load
C. Boom length
D. Load height
Answer: Distance from center of rotation to load
Rationale: Working radius affects load capacity and stability.
7. A side load on the boom is:
A. A vertical load
B. A load applied parallel to the boom
C. A load applied perpendicular to the boom
, D. A suspended load
Answer: A load applied perpendicular to the boom
Rationale: Side loading can cause structural damage and instability.
8. What is the function of a sheave?
A. Support outriggers
B. Guide wire rope
C. Control engine speed
D. Measure load weight
Answer: Guide wire rope
Rationale: Sheaves help direct and support wire rope movement.
9. When should a wire rope be replaced?
A. When it looks dirty
B. When broken wires exceed limits
C. Every month
D. Only when it snaps
Answer: When broken wires exceed limits
Rationale: Safety standards specify replacement criteria based on wear
and damage.
10.The boom angle indicator shows:
A. Load weight
B. Boom elevation angle
C. Wind speed
D. Engine RPM
Answer: Boom elevation angle
Rationale: This helps determine safe lifting capacity.
11.What hazard is associated with overhead power lines?
A. Fire only
B. Electrocution
C. Noise
D. Dust
Exam Questions And Correct Answers
(Verified Answers) Plus Rationales 2026
Q&A Instant Download Pdf
1. What is the primary purpose of a digger derrick?
A. Excavating trenches
B. Lifting and placing poles and materials
C. Compacting soil
D. Transporting personnel
Answer: Lifting and placing poles and materials
Rationale: Digger derricks are designed mainly for lifting loads such as
utility poles and equipment.
2. The load chart on a digger derrick provides information about:
A. Fuel consumption
B. Maximum allowable loads at given radii
C. Operator schedules
D. Maintenance intervals
Answer: Maximum allowable loads at given radii
Rationale: Load charts indicate safe lifting capacities based on boom
angle, length, and radius.
3. What is the center of gravity?
A. The heaviest part of a load
B. The geometric center of a load
, C. The point where weight is evenly distributed
D. The top of the load
Answer: The point where weight is evenly distributed
Rationale: The center of gravity is the balance point where the load’s
weight is evenly distributed.
4. Before operating a digger derrick, the operator must:
A. Call the supervisor
B. Inspect the equipment
C. Refuel the machine
D. Check weather reports only
Answer: Inspect the equipment
Rationale: Pre-operation inspections are required to ensure safe
operation.
5. Outriggers are used to:
A. Lift loads
B. Stabilize the machine
C. Increase speed
D. Reduce fuel consumption
Answer: Stabilize the machine
Rationale: Outriggers provide stability during lifting operations.
6. The working radius is defined as:
A. Distance from boom tip to ground
B. Distance from center of rotation to load
C. Boom length
D. Load height
Answer: Distance from center of rotation to load
Rationale: Working radius affects load capacity and stability.
7. A side load on the boom is:
A. A vertical load
B. A load applied parallel to the boom
C. A load applied perpendicular to the boom
, D. A suspended load
Answer: A load applied perpendicular to the boom
Rationale: Side loading can cause structural damage and instability.
8. What is the function of a sheave?
A. Support outriggers
B. Guide wire rope
C. Control engine speed
D. Measure load weight
Answer: Guide wire rope
Rationale: Sheaves help direct and support wire rope movement.
9. When should a wire rope be replaced?
A. When it looks dirty
B. When broken wires exceed limits
C. Every month
D. Only when it snaps
Answer: When broken wires exceed limits
Rationale: Safety standards specify replacement criteria based on wear
and damage.
10.The boom angle indicator shows:
A. Load weight
B. Boom elevation angle
C. Wind speed
D. Engine RPM
Answer: Boom elevation angle
Rationale: This helps determine safe lifting capacity.
11.What hazard is associated with overhead power lines?
A. Fire only
B. Electrocution
C. Noise
D. Dust
