Service Truck Crane Operator Flashcards

A service truck crane is rated at 6,000 lbs capacity at a 10-ft radius on outriggers fully extended. The operator needs to lift 5,200 lbs at a 12-ft radius with outriggers extended only to 75% of their full span. Which action is MOST appropriate before proceeding?

Answer: Consult the crane's load chart for the reduced outrigger span capacity at 12 ft and compare it to the 5,200 lb load

Load charts for service truck cranes include separate columns or charts for different outrigger configurations (fully extended, partially extended, and on rubber). Capacity is significantly reduced at 75% outrigger extension compared to full extension, and the capacity further decreases at a larger radius. The operator must verify the actual capacity under the exact conditions—reduced outrigger span AND 12-ft radius—before lifting. Proceeding based only on the full-extension, 10-ft rating would be unsafe and violates ASME B30.22.

During a pre-operational inspection of a service truck crane, the operator discovers that the load line has 3 broken wires in one strand within a length of 8 times the rope diameter, and 4 additional broken wires distributed across other strands in the same lay length. Under ASME B30.22, what is the correct action?

Answer: Remove the rope from service immediately — both criteria for removal are independently met

ASME B30.22 specifies that wire rope must be removed from service if there are 6 or more broken wires in one rope lay, OR 3 or more broken wires in one strand in one rope lay. In this scenario, the 3 broken wires in a single strand independently meet the removal criterion, regardless of the distribution of the 4 additional broken wires. Either threshold triggers removal — both do not need to be exceeded simultaneously. Reducing capacity and continuing operation is never an acceptable response to a removal-from-service condition.

A service truck crane operator is setting up on a paved surface to lift a load. The outrigger pads provided are each 18 inches × 18 inches (324 sq in). The crane manufacturer's load chart indicates a maximum outrigger reaction force of 38,000 lbs on each outrigger for this pick. The pavement is rated at 100 psi. What is the MINIMUM required outrigger pad area per pad to stay within the pavement rating?

Answer: 380 square inches

Ground bearing pressure equals force divided by area (P = F/A). To find the minimum required area: A = F/P = 38,000 lbs ÷ 100 psi = 380 square inches. The supplied 18×18 pads are only 324 sq in, which would produce 38,000 ÷ 324 ≈ 117 psi — exceeding the 100 psi pavement rating. Larger pads or cribbing to achieve at least 380 sq in of bearing area are required before lifting. Using undersized pads risks pavement failure and crane upset.

While swinging a load on a service truck crane, the operator notices the load begins to pendulum (swing freely). Which combination of operator actions BEST controls a pendulating load and is consistent with ASME B30.22 safe operating practices?

Answer: Stop the swing motion, hold the boom stationary, and have a qualified rigger use a tag line to control the load

A pendulating (freely swinging) load represents a loss of load control. The correct response is to cease motion immediately, hold the boom stationary, and use a tag line managed by a qualified person on the ground to arrest the swing. Increasing swing speed is dangerous and amplifies dynamic forces. Rapidly lowering the load can increase pendulum velocity and cause the load to strike structures or personnel. Extending the boom reduces rated capacity and does not reliably dampen a pendulum — it can worsen the situation. Tag lines must be attached before the lift begins per ASME B30.22.

A service truck crane is working within 20 feet of a 7,200-volt (7.2 kV) distribution power line. The utility owner has NOT de-energized or provided insulating barriers. Under OSHA 1926.1408 Table A, what is the minimum required clearance the crane and its load must maintain from this line?

Answer: 10 feet

OSHA 1926.1408 Table A establishes minimum approach distances for energized overhead power lines. For voltages up to 50 kV, the required clearance is 10 feet. Since 7,200 volts (7.2 kV) falls below 50 kV, the minimum required distance between the crane (or its load/rigging/line) and the energized line is 10 feet. This clearance applies to all parts of the equipment, the load line, the load, and any rigging — not just the boom tip. Without utility confirmation of de-energization, the operator must maintain this distance at all times.

A service truck crane operator is performing a critical lift where the load weight is 95% of the crane's rated capacity at the given radius. The lift plan requires the operator to swing 180° with the load. During the swing, the operator observes the load line angle (side pull) is approximately 5° off vertical due to the load's center of gravity shifting. What is the MOST accurate assessment of this situation?

Answer: The lift must be stopped — side loading is prohibited under ASME B30.22 and can overturn the crane at near-rated capacities

ASME B30.22 explicitly prohibits side loading (pulling the load line out of vertical) on service truck cranes. Load charts are based on plumb (vertical) line pulls. At 95% of rated capacity, even a small side load introduces lateral forces that the crane's structure is not designed to handle, dramatically increasing the risk of structural failure or overturning. The correct action is to stop the lift, re-rig the load so the hook is directly above the load's center of gravity, and ensure the line is plumb before proceeding. There is no acceptable tolerance for side loading at near-rated capacities.