Crane Lift of a Steel Coil
On a longshoring job, a crane is lifting a 12-ton steel coil from a barge to a dock. The coil is rigged with two synthetic slings in a basket hitch. The crane operator is 150 feet away and cannot see the load; a signalperson is using hand signals, but a third worker walks under the suspended coil to steady it. Wind gusts are 25 mph. The crane's load chart at the working radius shows a capacity of 15 tons with the current boom length and outriggers. The rigging crew wants to continue because the coil is only 80% of capacity. A sling tag is frayed and unreadable; one sling has a visible cut. The signalperson is also the rigger and is standing near the load.
1. Identify the unsafe conditions and decide whether the lift should proceed.
Read the worked answer
The lift should not proceed. A worker under a suspended load is exposed to crushing if the rigging fails; that is a stop-work condition. The sling with a cut and an unreadable tag cannot be verified, so its capacity is unknown. The signalperson doubling as rigger and standing near the load creates both communication and struck-by hazards. Wind at 25 mph can affect the load and may exceed the crane manufacturer's limit; the 15-ton chart capacity at 80% does not account for wind, dynamic effects, or side loading. The employer should lower the load to a safe location, clear personnel from beneath it, and stop the lift until the rigging is inspected and replaced as needed. The 80% figure is not a safety margin that overrides these defects.
2. What must be verified about the rigging and crane before the lift?
Read the worked answer
Before resuming, a qualified rigger should inspect the slings, verify tags and capacities, and confirm the hitch and sling angles. The 12-ton load is 24,000 pounds; with two slings in a basket hitch, the tension in each sling increases as the angle from horizontal decreases, so the rigger must use the manufacturer's capacity chart, not just the vertical rating. The operator must verify the load chart for the actual radius, boom length, outrigger configuration, and wind; if wind exceeds the manufacturer's limit, stop. The crane must be level, on stable ground, with outriggers fully extended. The signalperson must be qualified, positioned to see both load and operator, and use agreed signals. The area under the load must be barricaded. The damaged sling must be removed from service.
3. What are the signalperson and rigger responsibilities, and why does combining them matter?
Read the worked answer
The signalperson directs the operator and must be qualified, use standard signals, and maintain a clear view; the rigger selects, inspects, and attaches the rigging and ensures the load is balanced. Combining both roles can work only if the person can do both safely from a position outside the fall/load zone. Here, the signalperson is also the rigger and is standing near the load, so a rigging problem could injure the person who is supposed to be controlling the lift. The employer should assign a separate signalperson or reposition the rigger, establish radio or hand-signal communication, and ensure no one stands under the load. The employer should also confirm the operator can see the signalperson or use an alternative communication method. These roles are safety-critical, not clerical.