How do you determine the safe working radius for a lift?

• A. Rely on general guidelines rather than precise load charts.
• B. Use improvised measurements at the worksite to estimate the radius.
• C. Use the crane’s load chart for the chosen boom length and configuration to ensure the radius lies within capacity.
• D. Assume the radius is within capacity if the load is light.

Answer: (C)

Understanding how radius affects lifting capacity is essential. The crane’s load chart provides the official data for a specific boom length and configuration, showing how much load can be safely lifted at each radius. To determine a safe working radius, you select the exact boom setup you’ll use and read the chart at the corresponding radius to ensure the planned load is within the chart’s capacity. If the planned lift would exceed the chart at that radius, you must adjust the configuration—such as using a shorter radius, different boom length, or additional counterweight—and re-check. Other safety factors like wind, rigging, ground conditions, and outrigger setup also influence capacity, so the chart must be consulted under the actual conditions. Relying on general guidelines, improvised measurements, or assuming safety based on a light load can be unsafe because capacity varies with radius and configuration, not just with the weight alone.