Lifting Operations
Control of the lift
Before hoisting, confirm load weight (calculated or weighed, not guessed), rigging selection, path of travel, landing point, and communication. Tower crane work is usually blind, so a qualified signalperson on a dedicated radio channel is essential. Only one designated signalperson directs the operator, but a stop signal from anyone must be obeyed immediately. Hand signals must be standard and unambiguous; radios get a functional check and a channel agreed at the pre-lift briefing.
Executing the lift
Lift clear, hold, and check balance and rigging before slewing. Control swing with slow starts and stops to limit pendulum action; taglines steady the load. Never drag, side-pull, or yard a load with the hoist. Do not pass loads over personnel. Do not leave the controls with a load suspended. Keep the hoist drum from running out of wraps. Suspend operations in wind, lightning, or icing beyond the manufacturer's limits, and know the emergency lowering procedure if power is lost.
Critical lifts
Critical lifts - near chart capacity, over occupied areas, unusual rigging, or high-consequence - get a written lift plan, engineered rigging, and a pre-lift meeting.
Traps
Accepting direction from multiple people; assuming the operator can judge blind clearance; treating a tagline as optional on a long load; and forgetting the load's own wind area when a panel acts like a sail.
Worked example
Rule of thumb: total lifting-system weight should stay comfortably inside the chart - plan the lift to no more than about 75% of charted capacity at that radius for routine work, and treat anything approaching 90% as a critical lift requiring a written plan and a supervisor's sign-off.