What is meant by the term "two blocking"?

The term "two blocking" refers specifically to the condition where the load block, which is part of the hoisting system, makes contact with the boom point sheaves. This scenario poses a significant risk, as it can lead to structural damage to the crane or the load handling equipment, and may even result in a catastrophic failure.

Understanding this situation is crucial for riggers and operators, as it indicates that the boom is being over-extended, or that there may be improper lifting practices taking place. Recognizing the signs of two blocking and implementing safety measures to prevent it is essential in ensuring safe operation standards in lifting operations. In contrast, the other options refer to different contexts that don't align with the definition or work operating procedures related to two blocking.