MOBILE CRANE EXAM PREP 2026/2027 | 150 Questions |
Verified Answers | 100% Correct | Pass Guaranteed - A+
Graded
SECTION 1: Crane Setup & Site Assessment (Q1–Q20)
Q1: A mobile crane is being set up on a compacted gravel surface for a lift requiring
maximum chart capacity. According to ASME B30.5, what is the maximum allowable
slope for the crane to be considered "level" during setup?
A. 2% grade in any direction
B. 1.5% grade in any direction
C. 1% grade in any direction [CORRECT]
D. 0.5% grade in any direction
Correct Answer: C
Rationale: ASME B30.5 requires mobile cranes to be set up within 1% of level to ensure
rated capacities are valid. Options A and B exceed the allowable slope, while D is more
restrictive than the standard requires.
Q2: During site assessment, the operator discovers underground utilities marked with
red paint. What does red typically indicate?
A. Telecommunication lines
B. Electric power lines [CORRECT]
C. Water lines
D. Sewer lines
Correct Answer: B
Rationale: The APWA uniform color code designates red for electric power lines. Blue
indicates water, orange indicates telecommunications, and green indicates sewer lines.
Q3: A crane operator is setting up near a 345kV energized power line. What is the
minimum required clearance according to OSHA 1926.1409?
A. 20 feet
,B. 25 feet
C. 30 feet
D. 35 feet [CORRECT]
Correct Answer: D
Rationale: OSHA 1926.1409 Table A requires a minimum clearance of 35 feet for power
lines rated over 250kV up to 350kV. Options A, B, and C represent clearances for lower
voltage categories.
Q4: Ground bearing pressure calculations must account for which factor when
determining required cribbing area?
A. Only the weight of the crane itself
B. The total weight of the crane plus the lifted load divided by the outrigger float area
[CORRECT]
C. The boom weight only
D. The load weight divided by the crane's tire contact area
Correct Answer: B
Rationale: Ground bearing pressure is calculated by dividing the total reaction force
(crane weight plus load effects) by the effective bearing area (outrigger float plus
cribbing). Options A, C, and D omit critical components of the calculation.
Q5: Which soil type presents the highest risk for crane setup without adequate cribbing?
A. Compacted clay
B. Bedrock
C. Loose uncompacted fill over recently buried trenches [CORRECT]
D. Engineered concrete pad
Correct Answer: C
Rationale: Loose uncompacted fill over trenches creates voids and non-uniform support,
leading to potential catastrophic settlement. Options A, B, and D represent generally
acceptable or engineered support surfaces.
Q6: When performing a site assessment, the operator notices the ground slopes 2%
toward the south side. What is the proper response?
A. Proceed with the lift but reduce capacity by 25%
B. Position the crane so the boom operates over the uphill side only
C. Use additional cribbing or mats to achieve level within 1% before lifting [CORRECT]
D. Extend the outriggers an extra 6 inches on the downhill side
,Correct Answer: C
Rationale: ASME B30.5 requires the crane to be within 1% of level for rated capacity.
Simply operating over the uphill side (B) or extending outriggers unevenly (D) does not
address the level requirement, and there is no standard 25% reduction (A) for slope.
Q7: What is the primary purpose of cribbing under outrigger floats?
A. To increase the crane's overall height
B. To distribute the outrigger load over a larger area to reduce ground bearing pressure
[CORRECT]
C. To prevent the outriggers from sinking into asphalt only
D. To provide a convenient storage location for rigging hardware
Correct Answer: B
Rationale: Cribbing increases the effective bearing area, reducing ground bearing
pressure to prevent settlement or failure. Options A, C, and D do not represent the
primary engineering purpose of cribbing.
Q8: An operator is setting up a mobile crane on asphalt in a parking lot. What additional
concern must be addressed?
A. Asphalt is always sufficient for any crane load
B. The thickness of the asphalt and the condition of the base material underneath
[CORRECT]
C. Only the ambient temperature matters
D. Asphalt requires no cribbing under any circumstances
Correct Answer: B
Rationale: Asphalt strength depends on thickness and the supporting base material; thin
asphalt over weak base can fail under concentrated outrigger loads. Options A and D
are dangerous assumptions, and temperature (C) is secondary to structural capacity.
Q9: The "center of rotation" on a mobile crane is defined as:
A. The geometric center of the crane's cab
B. The center of the turntable rotation [CORRECT]
C. The midpoint between the front and rear axles
D. The center of gravity of the counterweight
Correct Answer: B
, Rationale: The center of rotation is the vertical axis about which the upperworks rotate,
located at the center of the turntable. Options A, C, and D describe other crane reference
points but not the center of rotation.
Q10: Before setting up a crane, the operator must verify that the ground conditions are
adequate. Who has the ultimate responsibility for ensuring ground conditions are
sufficient?
A. The site superintendent only
B. The crane operator only
C. The controlling entity (site manager/owner) with the operator's verification
[CORRECT]
D. The utility locator service
Correct Answer: C
Rationale: OSHA 1926.1402 requires the controlling entity to provide adequate ground
conditions, while the operator must verify them before setup. Options A and B place
responsibility on only one party, and D is unrelated to ground bearing capacity.
Q11: When calculating ground bearing pressure, the "loaded radius" is measured from:
A. The center of rotation to the center of gravity of the load [CORRECT]
B. The center of rotation to the hook block only
C. The outrigger pad to the load
D. The rear of the crane to the load
Correct Answer: A
Rationale: Operating radius is defined as the horizontal distance from the center of
rotation to the center of gravity of the suspended load. Options B, C, and D describe
incorrect measurement points.
Q12: A crane is being set up in an area where the soil bearing capacity is 2,500 psf. The
calculated outrigger reaction is 100,000 lbs. What is the minimum required cribbing
area per outrigger?
A. 20 square feet
B. 30 square feet
C. 40 square feet [CORRECT]
D. 50 square feet
Correct Answer: C
Verified Answers | 100% Correct | Pass Guaranteed - A+
Graded
SECTION 1: Crane Setup & Site Assessment (Q1–Q20)
Q1: A mobile crane is being set up on a compacted gravel surface for a lift requiring
maximum chart capacity. According to ASME B30.5, what is the maximum allowable
slope for the crane to be considered "level" during setup?
A. 2% grade in any direction
B. 1.5% grade in any direction
C. 1% grade in any direction [CORRECT]
D. 0.5% grade in any direction
Correct Answer: C
Rationale: ASME B30.5 requires mobile cranes to be set up within 1% of level to ensure
rated capacities are valid. Options A and B exceed the allowable slope, while D is more
restrictive than the standard requires.
Q2: During site assessment, the operator discovers underground utilities marked with
red paint. What does red typically indicate?
A. Telecommunication lines
B. Electric power lines [CORRECT]
C. Water lines
D. Sewer lines
Correct Answer: B
Rationale: The APWA uniform color code designates red for electric power lines. Blue
indicates water, orange indicates telecommunications, and green indicates sewer lines.
Q3: A crane operator is setting up near a 345kV energized power line. What is the
minimum required clearance according to OSHA 1926.1409?
A. 20 feet
,B. 25 feet
C. 30 feet
D. 35 feet [CORRECT]
Correct Answer: D
Rationale: OSHA 1926.1409 Table A requires a minimum clearance of 35 feet for power
lines rated over 250kV up to 350kV. Options A, B, and C represent clearances for lower
voltage categories.
Q4: Ground bearing pressure calculations must account for which factor when
determining required cribbing area?
A. Only the weight of the crane itself
B. The total weight of the crane plus the lifted load divided by the outrigger float area
[CORRECT]
C. The boom weight only
D. The load weight divided by the crane's tire contact area
Correct Answer: B
Rationale: Ground bearing pressure is calculated by dividing the total reaction force
(crane weight plus load effects) by the effective bearing area (outrigger float plus
cribbing). Options A, C, and D omit critical components of the calculation.
Q5: Which soil type presents the highest risk for crane setup without adequate cribbing?
A. Compacted clay
B. Bedrock
C. Loose uncompacted fill over recently buried trenches [CORRECT]
D. Engineered concrete pad
Correct Answer: C
Rationale: Loose uncompacted fill over trenches creates voids and non-uniform support,
leading to potential catastrophic settlement. Options A, B, and D represent generally
acceptable or engineered support surfaces.
Q6: When performing a site assessment, the operator notices the ground slopes 2%
toward the south side. What is the proper response?
A. Proceed with the lift but reduce capacity by 25%
B. Position the crane so the boom operates over the uphill side only
C. Use additional cribbing or mats to achieve level within 1% before lifting [CORRECT]
D. Extend the outriggers an extra 6 inches on the downhill side
,Correct Answer: C
Rationale: ASME B30.5 requires the crane to be within 1% of level for rated capacity.
Simply operating over the uphill side (B) or extending outriggers unevenly (D) does not
address the level requirement, and there is no standard 25% reduction (A) for slope.
Q7: What is the primary purpose of cribbing under outrigger floats?
A. To increase the crane's overall height
B. To distribute the outrigger load over a larger area to reduce ground bearing pressure
[CORRECT]
C. To prevent the outriggers from sinking into asphalt only
D. To provide a convenient storage location for rigging hardware
Correct Answer: B
Rationale: Cribbing increases the effective bearing area, reducing ground bearing
pressure to prevent settlement or failure. Options A, C, and D do not represent the
primary engineering purpose of cribbing.
Q8: An operator is setting up a mobile crane on asphalt in a parking lot. What additional
concern must be addressed?
A. Asphalt is always sufficient for any crane load
B. The thickness of the asphalt and the condition of the base material underneath
[CORRECT]
C. Only the ambient temperature matters
D. Asphalt requires no cribbing under any circumstances
Correct Answer: B
Rationale: Asphalt strength depends on thickness and the supporting base material; thin
asphalt over weak base can fail under concentrated outrigger loads. Options A and D
are dangerous assumptions, and temperature (C) is secondary to structural capacity.
Q9: The "center of rotation" on a mobile crane is defined as:
A. The geometric center of the crane's cab
B. The center of the turntable rotation [CORRECT]
C. The midpoint between the front and rear axles
D. The center of gravity of the counterweight
Correct Answer: B
, Rationale: The center of rotation is the vertical axis about which the upperworks rotate,
located at the center of the turntable. Options A, C, and D describe other crane reference
points but not the center of rotation.
Q10: Before setting up a crane, the operator must verify that the ground conditions are
adequate. Who has the ultimate responsibility for ensuring ground conditions are
sufficient?
A. The site superintendent only
B. The crane operator only
C. The controlling entity (site manager/owner) with the operator's verification
[CORRECT]
D. The utility locator service
Correct Answer: C
Rationale: OSHA 1926.1402 requires the controlling entity to provide adequate ground
conditions, while the operator must verify them before setup. Options A and B place
responsibility on only one party, and D is unrelated to ground bearing capacity.
Q11: When calculating ground bearing pressure, the "loaded radius" is measured from:
A. The center of rotation to the center of gravity of the load [CORRECT]
B. The center of rotation to the hook block only
C. The outrigger pad to the load
D. The rear of the crane to the load
Correct Answer: A
Rationale: Operating radius is defined as the horizontal distance from the center of
rotation to the center of gravity of the suspended load. Options B, C, and D describe
incorrect measurement points.
Q12: A crane is being set up in an area where the soil bearing capacity is 2,500 psf. The
calculated outrigger reaction is 100,000 lbs. What is the minimum required cribbing
area per outrigger?
A. 20 square feet
B. 30 square feet
C. 40 square feet [CORRECT]
D. 50 square feet
Correct Answer: C
