NCCCO Mobile Crane Operator Core
Practice Test: Site, Operations, and
Load Charts
Hidden underground voids -Answer--Old tanks or loose fill that could collapse under
the crane.
Overhead power lines -Answer--Obstructions in the crane's swing area that must be
considered.
Ground surface conditions -Answer--Conditions such as slopes or soft/uncompacted
soil that affect crane setup.
Controlling entity -Answer--The party primarily responsible for ensuring adequate
ground conditions for safe crane operations.
Ground pressure information -Answer--Data that must be checked against soil
capacity to verify ground support for the crane.
Level percentage for crane setup -Answer--A crane must be set up within 1% of level
for its load chart ratings to remain valid.
Supporting materials under outrigger pads -Answer--Mats or blocking used to reduce
ground pressure by distributing the load.
Swing radius safety -Answer--Accessible areas must be barricaded to prevent
anyone from entering and getting struck or crushed.
Partially extended outriggers -Answer--If one outrigger cannot be fully extended, use
the 'on rubber' load chart.
Excavation placement rule -Answer--Keep outriggers or tracks back from the edge at
least the same distance as the depth of the excavation.
Crane wheel positioning -Answer--The crane's wheels should be just barely off the
ground, relieved of the crane's weight.
, Sinking outrigger pad response -Answer--If an outrigger pad begins to sink, the
operator should stop the lift and re-set the crane on more stable ground.
Crawler crane ground bearing pressure -Answer--Moving a crawler crane from soft
ground to hard ground increases the ground pressure.
Timber blocking under crawler tracks -Answer--Placing timber blocking only under
the tips of tracks will not support the entire track.
Make the crane more stable -Answer--C. Make the crane less stable (reducing its
effective footprint)
Minimum clearance for cranes near power lines up to 50 kV -Answer--A. 10 feet (3
m)
Clearance distance for extremely high-voltage lines over 750 kV -Answer--C. 45 feet
Crane assembly and disassembly supervision -Answer--C. Directed by a qualified
Assembly/Disassembly (A/D) director who understands the process and hazards
Pre-lift requirements for crane operations -Answer--B. Review the planned lift
requirements, load weight, and site conditions with the site supervisor or lift director
Setting up a crane on a slope -Answer--B. Use cribbing or blocking under the
outriggers or tracks to level the crane as much as possible (within 1% level) before
lifting
Working near energized power lines -Answer--B. If it's necessary to work closer than
the mandated clearance to live power lines, the lines must be de-energized and
grounded or insulated, and a dedicated spotter should be used.
Standard hand signals for crane operation -Answer--C. Boom up
Authority to halt crane operation -Answer--B. The crane operator has the authority to
refuse or stop operations he/she deems unsafe
Most common cause of fatal crane operator accidents -Answer--B. Electrocution
(contact with power lines)
Riding on the crane's hook or load -Answer--D. Never - it is prohibited to carry
personnel on the hook or load (except in a properly designed man-basket under very
strict guidelines)
Climb down from the cab -Answer--Carefully get away from the crane.
Practice Test: Site, Operations, and
Load Charts
Hidden underground voids -Answer--Old tanks or loose fill that could collapse under
the crane.
Overhead power lines -Answer--Obstructions in the crane's swing area that must be
considered.
Ground surface conditions -Answer--Conditions such as slopes or soft/uncompacted
soil that affect crane setup.
Controlling entity -Answer--The party primarily responsible for ensuring adequate
ground conditions for safe crane operations.
Ground pressure information -Answer--Data that must be checked against soil
capacity to verify ground support for the crane.
Level percentage for crane setup -Answer--A crane must be set up within 1% of level
for its load chart ratings to remain valid.
Supporting materials under outrigger pads -Answer--Mats or blocking used to reduce
ground pressure by distributing the load.
Swing radius safety -Answer--Accessible areas must be barricaded to prevent
anyone from entering and getting struck or crushed.
Partially extended outriggers -Answer--If one outrigger cannot be fully extended, use
the 'on rubber' load chart.
Excavation placement rule -Answer--Keep outriggers or tracks back from the edge at
least the same distance as the depth of the excavation.
Crane wheel positioning -Answer--The crane's wheels should be just barely off the
ground, relieved of the crane's weight.
, Sinking outrigger pad response -Answer--If an outrigger pad begins to sink, the
operator should stop the lift and re-set the crane on more stable ground.
Crawler crane ground bearing pressure -Answer--Moving a crawler crane from soft
ground to hard ground increases the ground pressure.
Timber blocking under crawler tracks -Answer--Placing timber blocking only under
the tips of tracks will not support the entire track.
Make the crane more stable -Answer--C. Make the crane less stable (reducing its
effective footprint)
Minimum clearance for cranes near power lines up to 50 kV -Answer--A. 10 feet (3
m)
Clearance distance for extremely high-voltage lines over 750 kV -Answer--C. 45 feet
Crane assembly and disassembly supervision -Answer--C. Directed by a qualified
Assembly/Disassembly (A/D) director who understands the process and hazards
Pre-lift requirements for crane operations -Answer--B. Review the planned lift
requirements, load weight, and site conditions with the site supervisor or lift director
Setting up a crane on a slope -Answer--B. Use cribbing or blocking under the
outriggers or tracks to level the crane as much as possible (within 1% level) before
lifting
Working near energized power lines -Answer--B. If it's necessary to work closer than
the mandated clearance to live power lines, the lines must be de-energized and
grounded or insulated, and a dedicated spotter should be used.
Standard hand signals for crane operation -Answer--C. Boom up
Authority to halt crane operation -Answer--B. The crane operator has the authority to
refuse or stop operations he/she deems unsafe
Most common cause of fatal crane operator accidents -Answer--B. Electrocution
(contact with power lines)
Riding on the crane's hook or load -Answer--D. Never - it is prohibited to carry
personnel on the hook or load (except in a properly designed man-basket under very
strict guidelines)
Climb down from the cab -Answer--Carefully get away from the crane.
