What is generally acknowledged as the capacity limitation that separates a standard lift from a critical lift?

• A. 50%
• B. 75%
• C. 90%
• D. 100%

Answer: (B)

Think of a crane’s rated capacity as the safe limit for a lift at a given hook height and radius. In a standard, routine lift you stay well below that limit, leaving margin to absorb unexpected forces. When you use about three-quarters of that capacity, the margin shrinks significantly. Small changes in wind, rigging elongation, crane movement, or load sway can push you into an unsafe condition, so the operation becomes much riskier and much more dependent on careful planning. That increased risk and the need for tighter controls is why lifts around 75% of the rated capacity are treated as critical lifts. They typically require a formal lift plan, a dedicated lift director, and enhanced precautions. So the commonly acknowledged threshold that separates a standard lift from a critical lift is about 75% of the crane’s rated capacity.