What is the purpose of tag lines in mobile crane operations, and how many are typically used?

• A. To control load rotation and drift; typically two or more, depending on load shape and weight
• B. To provide power to the crane
• C. To measure load weight
• D. To secure the load with a quick-release

Answer: (A)

Tag lines are used to control load rotation and drift during lifts, giving ground personnel a direct way to influence the load’s orientation and keep it from swinging or rotating as it is moved. This control is crucial for safe, accurate placement, especially when the load is asymmetrical, windy, or when visibility is limited. The number of tag lines depends on the load’s shape and weight: two tag lines are typical for most lifts, positioned opposite each other to provide balanced control. For heavier or more awkward loads, additional tag lines may be used to allow control from more directions. The lines are coordinated with the crane operator and kept under tension to prevent unwanted movement, while avoiding interference with people or equipment.