NCCCO Tower Crane Operator Exam
Questions & Verified Answers with
Rationale Latest Edition 2026/2027
Question 1
According to ASME B30.3, how should an overhead power line
be treated prior to operating a tower crane in its vicinity?
A. Assumed to be completely de-energized if it looks old
B. Always considered to be energized until the power
utility or owner verifies positively that it is not energized
C. Treated as a low-voltage line safe for accidental touch
D. Safe to work around as long as the crane boom does not
physically touch it
CORRECT ANSWER: B
RATIONALE: Safety standards dictate that all power lines must
be treated as live and energized until explicit confirmation and
lockout/tagout verification are provided by the utility authority.
Question 2
What specific markings are required on high-tensile bolts used
for critical tower crane structural connections, such as tower
sections and the slewing ring support?
A. Manufacturer designation and a specific strength rating
B. Only the length and diameter dimensions
C. A colored painted dot representing the batch
, D. The maximum allowable crane capacity
CORRECT ANSWER: A
RATIONALE: High-tensile structural bolts must clearly display
the manufacturer's mark and strength grade designation to
ensure they match the structural engineering specifications.
Question 3
What is the minimum strength rating requirement for high-
tensile nuts used in conjunction with structural tower section
bolts?
A. Grade 5
B. Grade 8
C. Rating of 12
D. Rating of 2
CORRECT ANSWER: C
RATIONALE: High-tensile connections on tower cranes
undergo immense cyclic stress, requiring heavy-duty nuts rated
at 12 to match or exceed the bolt proof load.
Question 4
What surface marking is mandatory on washers used in high-
tensile structural bolt connections on tower cranes?
A. CR
B. HV
C. NC
D. TX
,CORRECT ANSWER: B
RATIONALE: Hardened washers marked with "HV" (High
Vickers hardness) are specifically manufactured to prevent
embedding and maintain correct clamp load under high bolt
tension.
Question 5
When ready to torque a high-tensile structural bolt connection
on a tower crane, what should be done to the threads?
A. Keep them completely dry and dusty
B. Coat them with heavy industrial grease or manufacturer-
approved thread lubricant
C. Apply permanent thread-locking glue
D. Clean them with water only
CORRECT ANSWER: B
RATIONALE: Lubricating the threads reduces friction
resistance, ensuring that the applied torque translates accurately
into the correct bolt stretch and tension limit.
Question 6
When tightening high-tensile bolt connections on a tower crane,
where should the tightening torque preferably be applied?
A. To the bolt head
B. To the nut
C. Simultaneously to both ends using an impact wrench
D. It does not matter which end is turned
, CORRECT ANSWER: B
RATIONALE: Applying torque to the nut prevents torsional
stress from twisting the bolt shank itself, achieving a truer
clamping force and tension measurement.
Question 7
When torquing down the foundation anchor bolts on a tower
crane, what position should the counter jib ideally be oriented in
relation to the bolts being checked?
A. 0 degrees from the bolt
B. 90 degrees away from the anchor base
C. 180 degrees directly opposite
D. Orientation has no effect on base torquing
CORRECT ANSWER: A
RATIONALE: Positioning the counter jib at 0 degrees aligns
balance points and weight distributions correctly relative to the
foundation anchor assembly during critical torquing phases.
Question 8
According to the NCCCO reference manual, how many full
safety turns (wraps) must be left on the hoist drum at a minimum
when the load hook is in its lowest possible position?
A. Exactly 1 turn
B. At least 2 turns
C. At least 3 turns
D. At least 5 turns
Questions & Verified Answers with
Rationale Latest Edition 2026/2027
Question 1
According to ASME B30.3, how should an overhead power line
be treated prior to operating a tower crane in its vicinity?
A. Assumed to be completely de-energized if it looks old
B. Always considered to be energized until the power
utility or owner verifies positively that it is not energized
C. Treated as a low-voltage line safe for accidental touch
D. Safe to work around as long as the crane boom does not
physically touch it
CORRECT ANSWER: B
RATIONALE: Safety standards dictate that all power lines must
be treated as live and energized until explicit confirmation and
lockout/tagout verification are provided by the utility authority.
Question 2
What specific markings are required on high-tensile bolts used
for critical tower crane structural connections, such as tower
sections and the slewing ring support?
A. Manufacturer designation and a specific strength rating
B. Only the length and diameter dimensions
C. A colored painted dot representing the batch
, D. The maximum allowable crane capacity
CORRECT ANSWER: A
RATIONALE: High-tensile structural bolts must clearly display
the manufacturer's mark and strength grade designation to
ensure they match the structural engineering specifications.
Question 3
What is the minimum strength rating requirement for high-
tensile nuts used in conjunction with structural tower section
bolts?
A. Grade 5
B. Grade 8
C. Rating of 12
D. Rating of 2
CORRECT ANSWER: C
RATIONALE: High-tensile connections on tower cranes
undergo immense cyclic stress, requiring heavy-duty nuts rated
at 12 to match or exceed the bolt proof load.
Question 4
What surface marking is mandatory on washers used in high-
tensile structural bolt connections on tower cranes?
A. CR
B. HV
C. NC
D. TX
,CORRECT ANSWER: B
RATIONALE: Hardened washers marked with "HV" (High
Vickers hardness) are specifically manufactured to prevent
embedding and maintain correct clamp load under high bolt
tension.
Question 5
When ready to torque a high-tensile structural bolt connection
on a tower crane, what should be done to the threads?
A. Keep them completely dry and dusty
B. Coat them with heavy industrial grease or manufacturer-
approved thread lubricant
C. Apply permanent thread-locking glue
D. Clean them with water only
CORRECT ANSWER: B
RATIONALE: Lubricating the threads reduces friction
resistance, ensuring that the applied torque translates accurately
into the correct bolt stretch and tension limit.
Question 6
When tightening high-tensile bolt connections on a tower crane,
where should the tightening torque preferably be applied?
A. To the bolt head
B. To the nut
C. Simultaneously to both ends using an impact wrench
D. It does not matter which end is turned
, CORRECT ANSWER: B
RATIONALE: Applying torque to the nut prevents torsional
stress from twisting the bolt shank itself, achieving a truer
clamping force and tension measurement.
Question 7
When torquing down the foundation anchor bolts on a tower
crane, what position should the counter jib ideally be oriented in
relation to the bolts being checked?
A. 0 degrees from the bolt
B. 90 degrees away from the anchor base
C. 180 degrees directly opposite
D. Orientation has no effect on base torquing
CORRECT ANSWER: A
RATIONALE: Positioning the counter jib at 0 degrees aligns
balance points and weight distributions correctly relative to the
foundation anchor assembly during critical torquing phases.
Question 8
According to the NCCCO reference manual, how many full
safety turns (wraps) must be left on the hoist drum at a minimum
when the load hook is in its lowest possible position?
A. Exactly 1 turn
B. At least 2 turns
C. At least 3 turns
D. At least 5 turns