NCCCO Service Truck Crane Operator — Questions and Answers
Question 1: A service truck crane (knuckle boom crane) is mounted on a truck bed. Before lifting, which setup step is most critical for safe operation?
- Deploy and level the outriggers on stable ground and verify all outrigger pads are fully seated (Correct answer)
- Engage the truck's parking brake only — outriggers are optional for light lifts
- Raise the truck body's dump box to counterbalance the crane load
- Point the truck so the crane rotates away from the cab
Correct answer: Deploy and level the outriggers on stable ground and verify all outrigger pads are fully seated
Outrigger deployment and leveling is mandatory before any lift on a service truck crane. Operating without outriggers, or on improperly seated outrigger pads, is the leading cause of truck crane tip-overs.
Service truck cranes operate from a narrow truck wheelbase. Their rated capacity charts are developed for outrigger-deployed configurations. The truck must be on firm, level ground, outriggers fully extended, and outrigger pads properly sized to spread the ground bearing load. Failure to properly deploy outriggers has caused numerous fatalities in the utility and construction industries.
Question 2: Under OSHA 1926 Subpart CC, which definition applies to a service truck crane with a rated capacity of 2,000 pounds or more?
- It is covered equipment requiring operators to be certified or qualified per OSHA 1926.1427 (Correct answer)
- It is exempt from Subpart CC because it is truck-mounted
- It requires only a commercial driver's license with crane endorsement
- It falls under Subpart N but not Subpart CC
Correct answer: It is covered equipment requiring operators to be certified or qualified per OSHA 1926.1427
OSHA 1926 Subpart CC applies to all cranes and derricks with a rated capacity over 2,000 lb used in construction, including truck-mounted service cranes (knuckle booms).
OSHA 1926.1400 defines coverage: Subpart CC applies to equipment rated at more than 2,000 lb used in construction. Service truck cranes (knuckle boom cranes, articulating cranes) that meet this threshold require certified or qualified operators per 1926.1427, pre-shift inspections per 1926.1412, and compliance with all Subpart CC requirements including power line safety clearances.
Question 3: A service truck crane operator notices the truck is on a slight slope and the outrigger on the downhill side is not fully contacting the ground. What should the operator do?
- Reposition the truck on level ground or pack the downhill outrigger with cribbing until all outriggers bear evenly before lifting (Correct answer)
- Proceed with the lift if the load is under 50% of rated capacity
- Extend only the uphill outriggers to compensate for the slope
- Use the truck's hydraulic suspension to level the platform
Correct answer: Reposition the truck on level ground or pack the downhill outrigger with cribbing until all outriggers bear evenly before lifting
All outriggers must be in firm contact with stable ground before lifting. An outrigger not bearing load provides no stability benefit and the crane operates as if that outrigger is absent, significantly reducing tipping resistance.
Outriggers that are not firmly planted do not contribute to crane stability. On a slope, the downhill outrigger may be extended but not touching due to ground drop-off. The operator must use appropriately sized cribbing or blocking under outrigger pads, or reposition to level ground. Operating with a floating outrigger can result in sudden tip-over without warning.
Question 4: What is the maximum permissible wire rope drum fleet angle for a service truck crane's hoisting drum?
- 1.5 to 2 degrees for smooth drums and up to 4 degrees for grooved drums, per manufacturer specifications (Correct answer)
- 10 degrees maximum for all drum types
- No limitation — fleet angle is not a safety-critical parameter
- 5 degrees maximum regardless of drum type
Correct answer: 1.5 to 2 degrees for smooth drums and up to 4 degrees for grooved drums, per manufacturer specifications
Fleet angle — the angle between the wire rope and the drum centerline — must stay within manufacturer limits to prevent rope crossover damage and uneven winding. Typical limits are 1.5-2 degrees for smooth drums and up to 4 degrees for grooved drums.
Fleet angle determines how wire rope winds onto the hoist drum. Excessive fleet angle causes rope crossover, which crushes rope strands and damages drum flanges. Per ASME B30.5 and manufacturer guidelines, smooth drums should not exceed 1.5-2 degrees and grooved drums can tolerate up to 4 degrees. Maintaining proper fleet angle is part of the operator's daily inspection responsibilities.
Question 5: A service truck crane is equipped with a load moment indicator (LMI). The LMI alarm sounds and a red light illuminates during a pick. What must the operator do?
- Stop adding load immediately, lower the load to safe ground, and assess whether the pick exceeded rated capacity (Correct answer)
- Override the alarm using the bypass switch and complete the pick at reduced speed
- Increase boom angle to decrease working radius and silence the alarm
- Reduce load line speed and proceed carefully
Correct answer: Stop adding load immediately, lower the load to safe ground, and assess whether the pick exceeded rated capacity
An LMI alarm indicates the crane is approaching or has exceeded rated capacity for the current configuration. The operator must stop, lower the load, and determine whether to reduce the load, adjust the configuration, or refuse the lift.
The LMI is a warning system, not a substitute for proper lift planning. When the alarm activates, further hoisting or increasing radius is prohibited. The operator must lower the load to a safe position, identify why the alarm triggered (load heavier than estimated, radius greater than planned, or incorrect configuration), correct the issue, and re-evaluate before attempting the lift again. Bypassing LMI alarms is prohibited by OSHA 1926.1416.
Question 6: Which document is required to be in the cab of a service truck crane and must be legible at all times during operations?
- Load chart and operator's manual for the specific crane make and model (Correct answer)
- The operator's NCCCO certification card only
- The current OSHA inspection placard
- The truck's commercial driver's license registration and insurance documents
Correct answer: Load chart and operator's manual for the specific crane make and model
OSHA 1926.1417 and ASME B30.5 require that the rated capacity charts (load charts) and operator's manual for the specific crane be kept in the cab and be legible. These are the operator's primary reference during every lift.
Per OSHA 1926.1417(c), the load charts and operator's manual must be in the cab or at the operator's station at all times. They must be specific to the crane being used — generic charts are not acceptable. Charts must be legible and easily accessible. Missing, illegible, or generic charts are OSHA violations and remove the operator's ability to verify safe working limits.
NCCCO Service Truck Crane Operator
A service truck crane (knuckle boom crane) is mounted on a truck bed.
Before lifting, which setup step is most critical for safe operation?