5.8.3 Tandem Lifting classified a ‘Critical Lift’
1) Where two cranes are required to raise a load, the whole operation must be supervised by one specially appointed competent person. It is recommended that the SWL of each crane for the required jib length and operating radius should be at least 25% in excess of the calculated share of the load to be handled by each crane during the tandem lift.
2) The complexities of this type of operation should be clearly appreciated and all necessary steps should be taken to ensure that neither machine takes more than its calculated share of the load, that neither machine becomes out of level and that the hoist ropes remain plumb.