A heavy lift is required in a congested urban construction site where space is limited. The excavator operator must place a 4,000 kg structural steel beam. The lift chart indicates that at a 5.0-metre radius over the front, the capacity is 4,500 kg, and at a 4.0-metre radius over the front, it is 5,500 kg. However, due to site constraints, the minimum achievable load radius for the lift is 4.8 metres. What is the most appropriate action for the operator, assuming no additional counterweights are available?

Question: A heavy lift is required in a congested urban construction site where space is limited. The excavator operator must place a 4,000 kg structural steel beam. The lift chart indicates that at a 5.0-metre radius over the front, the capacity is 4,500 kg, and at a 4.0-metre radius over the front, it is 5,500 kg. However, due to site constraints, the minimum achievable load radius for the lift is 4.8 metres. What is the most appropriate action for the operator, assuming no additional counterweights are available?

Answer options:

• Proceed with the lift, assuming the capacity at 4.8 metres is sufficiently greater than 4,000 kg. ✅ Consult the lift chart for a precise capacity value at 4.8 metres, if provided, or consider it unsafe.
• Extend the boom beyond 5.0 metres to test the machine's stability.
• Decrease the engine speed to reduce dynamic forces during the lift.

Correct answer: Consult the lift chart for a precise capacity value at 4.8 metres, if provided, or consider it unsafe.

Explanation: When dealing with critical lifts, it is essential to know the exact lifting capacity at the specific load radius, especially if it falls between two listed values. If the chart does not explicitly provide a capacity for 4.8 metres, it is best to consider it unsafe or consult a supervisor/engineer before proceeding. Assuming capacities or extending the boom without clear data is hazardous.