According to ASME 830.5, what option provides guidance for an operator when a radius indicator becomes inoperative?

The correct answer highlights the importance of maintaining safety and precise operations in crane work, specifically when a radius indicator fails. According to ASME standards, the operator must measure the radius to ensure the crane is operating within safe limits. This is critical not only for the safe handling of loads but also to prevent potential accidents due to improper load distribution or excessive loads beyond the crane's capacity.

In the event the radius indicator is inoperative, measuring the radius manually ensures that the operator has the correct and necessary information to make informed decisions, rather than relying on potentially erroneous data or experience alone, which may lead to unsafe practices. This emphasizes the priority of adhering to safety protocols and proper procedures in crane operations, as outlined by ASME 830.5.