NCCCO PROFESSIONAL
CERTIFICATION COMPREHENSIVE
TEST QUESTIONS AND ANSWERS
1. When calculating the net capacity of a crane, which of the following must be deducted
from the gross capacity?
A. The weight of the rigging, block, and any stowed jib
B. The weight of the load itself
C. The weight of the crane fuel
D. The weight of the counterweights
Answer: A
Conceptual Explanation: Net capacity is calculated by subtracting all deductions (rigging,
blocks, stowed or erected jibs, hooks) from the gross capacity listed in the load chart.
2. What is the effect of side loading on a crane boom?
A. It increases the lifting capacity
B. It reduces the radius of the load
C. It improves the stability of the crane
,D. It causes structural failure without warning
Answer: D
Conceptual Explanation: Side loading exerts forces the boom was not designed to handle,
leading to sudden structural failure rather than a predictable tipping condition.
3. According to OSHA 1926.1408, what is the minimum clearance for power lines rated up to
50kV when the voltage is unknown?
A. 10 feet
B. 15 feet
C. 20 feet
D. 50 feet
Answer: C
Conceptual Explanation: For power lines up to 50kV, OSHA requires a minimum
clearance of 10 feet, but if the voltage is unknown, the safe default distance is often cited as
20 feet under current 1926 subpart CC regulations for general safety clearance when
voltage is not confirmed.
4. When a crane is out of level by 3 degrees on a long boom, how much capacity can be lost?
A. Up to 50%
B. 10%
C. 5%
, D. No capacity is lost
Answer: A
Conceptual Explanation: Operating a crane out of level significantly increases side stress
and increases the radius, potentially reducing capacity by as much as 50% on long boom
configurations.
5. What is the standard safety factor for general-purpose rigging slings?
A. 3:1
B. 4:1
C. 10:1
D. 5:1
Answer: D
Conceptual Explanation: Most general rigging slings are manufactured with a 5:1 design
factor, meaning their ultimate breaking strength is five times their rated Load Limit.
6. Which signal is indicated by extending the arm, thumb pointing down, and flexing the
fingers in and out?
A. Raise the boom and lower the load
B. Lower the boom and raise the load
C. Stop everything
D. Telescope out
CERTIFICATION COMPREHENSIVE
TEST QUESTIONS AND ANSWERS
1. When calculating the net capacity of a crane, which of the following must be deducted
from the gross capacity?
A. The weight of the rigging, block, and any stowed jib
B. The weight of the load itself
C. The weight of the crane fuel
D. The weight of the counterweights
Answer: A
Conceptual Explanation: Net capacity is calculated by subtracting all deductions (rigging,
blocks, stowed or erected jibs, hooks) from the gross capacity listed in the load chart.
2. What is the effect of side loading on a crane boom?
A. It increases the lifting capacity
B. It reduces the radius of the load
C. It improves the stability of the crane
,D. It causes structural failure without warning
Answer: D
Conceptual Explanation: Side loading exerts forces the boom was not designed to handle,
leading to sudden structural failure rather than a predictable tipping condition.
3. According to OSHA 1926.1408, what is the minimum clearance for power lines rated up to
50kV when the voltage is unknown?
A. 10 feet
B. 15 feet
C. 20 feet
D. 50 feet
Answer: C
Conceptual Explanation: For power lines up to 50kV, OSHA requires a minimum
clearance of 10 feet, but if the voltage is unknown, the safe default distance is often cited as
20 feet under current 1926 subpart CC regulations for general safety clearance when
voltage is not confirmed.
4. When a crane is out of level by 3 degrees on a long boom, how much capacity can be lost?
A. Up to 50%
B. 10%
C. 5%
, D. No capacity is lost
Answer: A
Conceptual Explanation: Operating a crane out of level significantly increases side stress
and increases the radius, potentially reducing capacity by as much as 50% on long boom
configurations.
5. What is the standard safety factor for general-purpose rigging slings?
A. 3:1
B. 4:1
C. 10:1
D. 5:1
Answer: D
Conceptual Explanation: Most general rigging slings are manufactured with a 5:1 design
factor, meaning their ultimate breaking strength is five times their rated Load Limit.
6. Which signal is indicated by extending the arm, thumb pointing down, and flexing the
fingers in and out?
A. Raise the boom and lower the load
B. Lower the boom and raise the load
C. Stop everything
D. Telescope out
