NCCCO Mobile Crane Operator Test 1 5 — Questions and Answers
Question 1: A mobile crane's load chart shows a capacity of 40,000 lbs at a 30-foot radius with outriggers fully extended. If the operator must work at the same radius with outriggers retracted (on rubber tires), the operator should expect the capacity to:
- Remain the same because the radius has not changed
- Increase because rubber tires absorb shock better than outriggers
- Decrease significantly, often to 75% or less of the outrigger rating (Correct answer)
- Double, because two axles share the load instead of four outriggers
Correct answer: Decrease significantly, often to 75% or less of the outrigger rating
On-rubber (tire) capacities are substantially lower than outrigger capacities because the crane's stability is greatly reduced without outriggers deployed.
Question 2: Which document specifies the inspection intervals and criteria for wire rope used on a mobile crane?
- OSHA 1926.550 general construction standard
- ASME B30.5 and the wire rope manufacturer's specifications (Correct answer)
- The rigging crew's daily safety briefing checklist
- The crane's annual insurance inspection report
Correct answer: ASME B30.5 and the wire rope manufacturer's specifications
ASME B30.5 and the wire rope manufacturer's documentation govern inspection frequencies and discard criteria for crane wire rope.
Question 3: When should a crane operator perform a pre-operational inspection?
- Once per week before the first shift of the week
- At the start of each shift before the crane is placed in service (Correct answer)
- Only after the crane has been relocated to a new jobsite
- Monthly, as required by the OSHA crane standard
Correct answer: At the start of each shift before the crane is placed in service
OSHA 1926.1412 and ASME B30.5 require a qualified operator to perform a pre-shift inspection before each day or shift of crane use.
Question 4: A signal person is required during crane operations whenever the operator:
- Is lifting more than 50% of the crane's rated capacity
- Does not have a clear and direct view of the load or the load's path of travel (Correct answer)
- Is operating within 100 feet of any structure
- Exceeds 10 mph wind speed during a pick
Correct answer: Does not have a clear and direct view of the load or the load's path of travel
OSHA 1926.1419 requires a signal person whenever the operator's view of the load or path of travel is obstructed.
Question 5: What is the maximum allowable out-of-level condition for most mobile crane setups according to manufacturer specifications?
- 5 degrees in any direction
- 3 degrees in any direction
- 1 degree in any direction (Correct answer)
- 0.5 degrees in any direction
Correct answer: 1 degree in any direction
Most crane manufacturers specify the crane must be within 1 degree of level (some specify less) for the load chart to be valid.
Question 6: Which of the following wire rope conditions requires immediate removal from service?
- Slight surface rust on the outer strands
- Six or more broken wires in one rope lay or three or more broken wires in one strand (Correct answer)
- Minor kinking that straightens when tension is applied
- Lubrication that appears dry on the outer surface
Correct answer: Six or more broken wires in one rope lay or three or more broken wires in one strand
ASME B30.5 and OSHA 1926.1413 mandate removing wire rope with six or more broken wires per lay or three or more per strand.
Question 7: During a tandem lift (two cranes lifting one load), who is responsible for directing the overall lift?
- The operator of the larger crane automatically assumes control
- A qualified lift director or designated person must coordinate the entire operation (Correct answer)
- Each operator independently manages their portion of the load
- The rigging foreman controls both cranes through the same signal person
Correct answer: A qualified lift director or designated person must coordinate the entire operation
ASME B30.5 requires a qualified lift director to plan and coordinate all aspects of a tandem lift due to the increased complexity and risk.
NCCCO Mobile Crane Operator Test 1 5
A mobile crane's load chart shows a capacity of 40,000 lbs at a 30-foot radius with outriggers fully extended.
If the operator must work at the same radius with outriggers retracted (on rubber tires), the operator should expect the capacity to: