An excavator operator is planning to lift a 3,000 kg precast concrete slab using a 20-tonne class excavator. The lift chart indicates that at a 6-metre load radius, the maximum allowable lifting capacity over the side is 3,500 kg, and over the front is 4,000 kg. The operator positions the excavator to lift the slab directly over its side. What is the maximum height the slab can be safely lifted at this radius?

Question: An excavator operator is planning to lift a 3,000 kg precast concrete slab using a 20-tonne class excavator. The lift chart indicates that at a 6-metre load radius, the maximum allowable lifting capacity over the side is 3,500 kg, and over the front is 4,000 kg. The operator positions the excavator to lift the slab directly over its side. What is the maximum height the slab can be safely lifted at this radius?

Answer options:

• The lift chart implicitly includes height variations at a given radius. ✅ The maximum height is not the primary limiting factor in this specific scenario.
• The lift chart indicates a specific height that must be adhered to.
• The maximum lifting height can be determined by interpolating between capacity values.

Correct answer: The maximum height is not the primary limiting factor in this specific scenario.

Explanation: In this scenario, the primary concern is the load capacity at the given radius, not the height. Lift charts generally specify capacities at various radii, and as long as the load is within the capacity for that radius, the height is often less of a direct limiting factor unless specified otherwise or the machine's maximum reach is exceeded. The other options are incorrect because lift charts prioritize radius and load, not a specific height limitation at a given radius, unless mentioned.