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NCCCO Mobile Crane Certification – 300
Questions, Answers & Load Chart Solutions
1. What is the minimum distance required from an overhead power line rated 50 kV to
any part of the crane or load?
a. 6 feet
b. 10 feet
c. 15 feet
d. 20 feet
Answer: b. 10 feet
OSHA 1926.1408 requires 10 feet for lines up to 50 kV, plus 4 inches per
additional 10 kV.
2. Ground bearing pressure is calculated by dividing the total crane weight by the:
a. Area of the supporting surface
b. Number of outriggers
c. Crane wheelbase
d. Boom length
Answer: a. Area of the supporting surface
Ground pressure = weight ÷ contact area. Larger area reduces pressure and
improves stability.
3. Cribbing used under outrigger floats must:
a. Be made of metal only
b. Be at least 12 inches thick
c. Be placed on firm, level ground and have sufficient surface area
d. Be painted yellow for visibility
Answer: c. Be placed on firm, level ground and have sufficient surface area
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Cribbing must distribute load safely. Firm ground and adequate surface prevent
sinking or shifting.
4. When setting up on a slope, the crane manufacturer's manual typically requires the
slope not to exceed:
a. 0.5% grade
b. 1% grade
c. 3% grade
d. 5% grade
Answer: b. 1% grade
Most manufacturers limit setup slope to 1% (1 foot per 100 feet). Exceeding this
risks instability.
5. The swing radius of the crane must be barricaded to prevent:
a. The crane from tipping
b. Personnel from entering the area during rotation
c. The load from swinging
d. Wind from affecting the boom
Answer: b. Personnel from entering the area during rotation
OSHA mandates barricading the swing radius to protect workers from being
struck by the rotating superstructure.
6. Soft ground conditions require the use of:
a. Smaller outrigger pads
b. Larger outrigger pads or mats
c. More counterweight
d. A shorter boom
Answer: b. Larger outrigger pads or mats
Larger pads increase footprint, reduce ground pressure, and prevent sinking or
tipping.
7. When setting up near an excavation, the crane should be positioned:
a. As close as possible to the edge
b. At least the depth of the excavation away from the edge
c. Directly over the excavation for better reach
d. Only on the
Q&A 1-300
, 3|Page
Here is the complete 300-question NCCCO Mobile Crane Exam bank with plain
text questions and choices. Only the answer and rationale are styled.
1–50: Core Knowledge – Site Conditions & Setup
1. What is the minimum distance required from an overhead power line rated 50 kV to
any part of the crane or load?
a. 6 feet
b. 10 feet
c. 15 feet
d. 20 feet
Answer: b. 10 feet
OSHA 1926.1408 requires 10 feet for lines up to 50 kV, plus 4 inches per
additional 10 kV.
2. Ground bearing pressure is calculated by dividing the total crane weight by the:
a. Area of the supporting surface
b. Number of outriggers
c. Crane wheelbase
d. Boom length
Answer: a. Area of the supporting surface
Ground pressure = weight ÷ contact area. Larger area reduces pressure and
improves stability.
3. Cribbing used under outrigger floats must:
a. Be made of metal only
b. Be at least 12 inches thick
c. Be placed on firm, level ground and have sufficient surface area
d. Be painted yellow for visibility
Answer: c. Be placed on firm, level ground and have sufficient surface area
Cribbing must distribute load safely. Firm ground and adequate surface prevent
sinking or shifting.
, 4|Page
4. When setting up on a slope, the crane manufacturer's manual typically requires the
slope not to exceed:
a. 0.5% grade
b. 1% grade
c. 3% grade
d. 5% grade
Answer: b. 1% grade
Most manufacturers limit setup slope to 1% (1 foot per 100 feet). Exceeding this
risks instability.
5. The swing radius of the crane must be barricaded to prevent:
a. The crane from tipping
b. Personnel from entering the area during rotation
c. The load from swinging
d. Wind from affecting the boom
Answer: b. Personnel from entering the area during rotation
OSHA mandates barricading the swing radius to protect workers from being
struck by the rotating superstructure.
6. Soft ground conditions require the use of:
a. Smaller outrigger pads
b. Larger outrigger pads or mats
c. More counterweight
d. A shorter boom
Answer: b. Larger outrigger pads or mats
Larger pads increase footprint, reduce ground pressure, and prevent sinking or
tipping.
7. When setting up near an excavation, the crane should be positioned:
a. As close as possible to the edge
b. At least the depth of the excavation away from the edge
c. Directly over the excavation for better reach
d. Only on the uphill side
Answer: b. At least the depth of the excavation away from the edge
OSHA requires the crane to be set back at least the depth of the excavation to
prevent cave-in and collapse.
NCCCO Mobile Crane Certification – 300
Questions, Answers & Load Chart Solutions
1. What is the minimum distance required from an overhead power line rated 50 kV to
any part of the crane or load?
a. 6 feet
b. 10 feet
c. 15 feet
d. 20 feet
Answer: b. 10 feet
OSHA 1926.1408 requires 10 feet for lines up to 50 kV, plus 4 inches per
additional 10 kV.
2. Ground bearing pressure is calculated by dividing the total crane weight by the:
a. Area of the supporting surface
b. Number of outriggers
c. Crane wheelbase
d. Boom length
Answer: a. Area of the supporting surface
Ground pressure = weight ÷ contact area. Larger area reduces pressure and
improves stability.
3. Cribbing used under outrigger floats must:
a. Be made of metal only
b. Be at least 12 inches thick
c. Be placed on firm, level ground and have sufficient surface area
d. Be painted yellow for visibility
Answer: c. Be placed on firm, level ground and have sufficient surface area
, 2|Page
Cribbing must distribute load safely. Firm ground and adequate surface prevent
sinking or shifting.
4. When setting up on a slope, the crane manufacturer's manual typically requires the
slope not to exceed:
a. 0.5% grade
b. 1% grade
c. 3% grade
d. 5% grade
Answer: b. 1% grade
Most manufacturers limit setup slope to 1% (1 foot per 100 feet). Exceeding this
risks instability.
5. The swing radius of the crane must be barricaded to prevent:
a. The crane from tipping
b. Personnel from entering the area during rotation
c. The load from swinging
d. Wind from affecting the boom
Answer: b. Personnel from entering the area during rotation
OSHA mandates barricading the swing radius to protect workers from being
struck by the rotating superstructure.
6. Soft ground conditions require the use of:
a. Smaller outrigger pads
b. Larger outrigger pads or mats
c. More counterweight
d. A shorter boom
Answer: b. Larger outrigger pads or mats
Larger pads increase footprint, reduce ground pressure, and prevent sinking or
tipping.
7. When setting up near an excavation, the crane should be positioned:
a. As close as possible to the edge
b. At least the depth of the excavation away from the edge
c. Directly over the excavation for better reach
d. Only on the
Q&A 1-300
, 3|Page
Here is the complete 300-question NCCCO Mobile Crane Exam bank with plain
text questions and choices. Only the answer and rationale are styled.
1–50: Core Knowledge – Site Conditions & Setup
1. What is the minimum distance required from an overhead power line rated 50 kV to
any part of the crane or load?
a. 6 feet
b. 10 feet
c. 15 feet
d. 20 feet
Answer: b. 10 feet
OSHA 1926.1408 requires 10 feet for lines up to 50 kV, plus 4 inches per
additional 10 kV.
2. Ground bearing pressure is calculated by dividing the total crane weight by the:
a. Area of the supporting surface
b. Number of outriggers
c. Crane wheelbase
d. Boom length
Answer: a. Area of the supporting surface
Ground pressure = weight ÷ contact area. Larger area reduces pressure and
improves stability.
3. Cribbing used under outrigger floats must:
a. Be made of metal only
b. Be at least 12 inches thick
c. Be placed on firm, level ground and have sufficient surface area
d. Be painted yellow for visibility
Answer: c. Be placed on firm, level ground and have sufficient surface area
Cribbing must distribute load safely. Firm ground and adequate surface prevent
sinking or shifting.
, 4|Page
4. When setting up on a slope, the crane manufacturer's manual typically requires the
slope not to exceed:
a. 0.5% grade
b. 1% grade
c. 3% grade
d. 5% grade
Answer: b. 1% grade
Most manufacturers limit setup slope to 1% (1 foot per 100 feet). Exceeding this
risks instability.
5. The swing radius of the crane must be barricaded to prevent:
a. The crane from tipping
b. Personnel from entering the area during rotation
c. The load from swinging
d. Wind from affecting the boom
Answer: b. Personnel from entering the area during rotation
OSHA mandates barricading the swing radius to protect workers from being
struck by the rotating superstructure.
6. Soft ground conditions require the use of:
a. Smaller outrigger pads
b. Larger outrigger pads or mats
c. More counterweight
d. A shorter boom
Answer: b. Larger outrigger pads or mats
Larger pads increase footprint, reduce ground pressure, and prevent sinking or
tipping.
7. When setting up near an excavation, the crane should be positioned:
a. As close as possible to the edge
b. At least the depth of the excavation away from the edge
c. Directly over the excavation for better reach
d. Only on the uphill side
Answer: b. At least the depth of the excavation away from the edge
OSHA requires the crane to be set back at least the depth of the excavation to
prevent cave-in and collapse.
