Which of the following is a Category 2 operator aid?

• A. Boom angle or radius indicator
• B. Jib angle indicator
• C. Boom length indicator
• D. Load weighing device

Answer: (A)

Category 2 operator aids are readouts that give the operator essential information about the crane’s current configuration to help make safe decisions, without automatically controlling the crane. The boom angle or radius indicator fits this role perfectly: it shows the actual geometry of the setup (how high the boom is and how far the load is from the crane), which directly influences the lifting capacity and safe operation. This kind of information helps the operator assess loads and limitations in real time.

The other options are less representative of Category 2. A jib angle indicator is more specialized for cranes with a jib and isn’t a universal Category 2 tool. A boom length indicator, while useful, is not the primary geometry readout relied on for capacity judgments in standard classifications. A load weighing device is typically part of higher-level protective systems that monitor and restrict operation, aligning more with Category 3.