The shaded area on a load chart indicates which category?

• A. Structural
• B. Operational
• C. Dynamic
• D. Permissible load

Answer: (A)

The shaded area on a load chart represents the crane’s structural capacity—the maximum load the crane’s structure can safely carry at each boom radius. It marks the strength limit of the equipment itself, independent of how you operate it or any dynamic effects from movement. Stay within this shaded region to keep the structure from being overstressed; lifting into or beyond it means approaching or exceeding the crane’s structural limits.

This region isn’t about operational ease or dynamic factors, which are considered separately on the chart. It also isn’t the permissible load after accounting for dynamic effects; instead, it shows the pure structural constraint of the crane.