What is required for signaling a crane when personnel platforms are being lifted?

When signaling a crane that is lifting personnel platforms, it is essential to have an anti two-block device in place. This device serves as a safety mechanism that prevents the crane cable from becoming overly tight and potentially slamming into the crane's boom. Two-blocking occurs when the hook block makes contact with the crane's boom or other structure, which can lead to catastrophic failure, including the risk of dropping the load or damaging equipment.

The use of an anti two-block device is particularly crucial when lifting personnel. It ensures that the load is being monitored continuously to prevent accidents that could endanger the lives of those working on the platform. This device contributes to enhanced safety protocols and is a critical requirement when personnel are being lifted in any operational scenario.

While multiple spotters, visual markers, and communication devices may also play significant roles in crane operation to provide additional safety and coordination, they do not specifically address the inherent risks associated with two-blocking incidents. Therefore, the anti two-block device stands out as the most direct and vital requirement for protecting personnel during such operations.