Which equipment is required if a telescopic boom crane is to be used to hoist a personnel platform?

The correct answer is that a boom angle indicator is required when using a telescopic boom crane to hoist a personnel platform. This piece of equipment is crucial because it provides real-time information about the angle of the crane's boom. Understanding the boom angle is essential for safety, as it impacts the crane's lifting capacity and stability. When a crane is used to lift personnel, knowing the boom angle helps ensure that the load is within safe operational limits and decreases the risk of overloading or tipping.

While a load cell could provide accurate weight measurements, it is not a requirement specifically for the operation of a personnel platform. Additional counterweights may enhance stability, but they are not mandated for all lift scenarios and depend on the crane's configuration and load. An operator with special certification is also important for personnel platform operations, but this is an operational requirement rather than a piece of equipment. Thus, the boom angle indicator stands out as specifically necessary for safe operation in this context.