Blind Lift Communication Failure
You are the signal person for a lift where the operator cannot see the load for the last 15 ft of travel because a wall blocks the view. The load is a 6,000 lb steel beam that must be landed on two anchor bolts, with a tolerance of about 1 inch. The crew has one radio and one set of hand signals. The operator is new to this site and has not worked with this crew. Mid-lift, the radio cuts out and the load is 3 ft above the bolts and drifting. A worker on the far side of the beam begins guiding it by hand.
1. What should the signal person do at the moment the radio cuts out, and why?
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Immediate action: Stop the lift. The signal person should give the stop signal by hand, and if the operator can see the signal person, hold the stop signal until communication is restored. If the operator cannot see the signal person either, the lift must be stopped by whatever means are available: a backup signal person in the operator's view, an air horn, or a predetermined emergency signal.
Why: With the radio out and the load blind to the operator, no one can direct the load. The load is 3 ft above the bolts and drifting, so an uncontrolled descent could land it off the bolts, tip it, or strike personnel. The operator must not continue on assumption.
Do not: have the worker on the far side take over signaling by hand unless that person is a designated signal person in the operator's view and the operator acknowledges. A worker guiding by hand is not a signal person and is now under or beside a suspended load.
After the stop: restore communication (spare battery, backup radio, or reposition a signal person in the operator's view), then resume with a clear plan.
2. Evaluate the worker guiding the beam by hand and state the correct control measures.
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Evaluation: Guiding a suspended load by hand puts the worker in the fall zone and in the pinch zone between the beam and the bolts. If the load shifts or the rigging slips, the worker has no escape. Hand guiding is sometimes permitted for a load that is essentially landed and stable, using a guide rope or a push stick, but not while the load is drifting 3 ft in the air with communication lost.
Correct measures:
- Stop the lift and move the worker clear of the fall zone.
- Use tag lines rigged before the lift to control rotation and drift from a safe distance.
- Use a guide rope or a push stick, not hands, for final positioning once the load is landed or nearly landed.
- Keep all personnel outside the fall zone until the load is set and the rigging is slack.
- Brief the crew on the fall zone and the no-hand-guiding rule before the lift.
Why it matters: The beam is 6,000 lb; a shift of a few inches can crush a hand or a body. The 1-inch tolerance is a reason for better control, not for hands on the load.
3. How should the lift plan and communication be set up to prevent this situation?
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Communication plan:
- Designate a primary signal person and a backup, both known to the operator.
- Agree on hand signals and a radio channel before the lift; test the radio and carry a spare battery.
- Establish an emergency stop signal that works without radio, such as an air horn or a signal person in view.
- The operator takes signals from one person only and stops on any unclear signal.
Blind lift plan:
- For the blind portion, position a signal person in the operator's view who can see the load, or use a radio relay.
- Plan the travel path and the landing sequence in steps, with a stop at each step.
- Use tag lines and a guide rope for final positioning.
- Brief the operator on the site, the load, and the crew, since the operator is new here.
Pre-lift meeting: Cover the load weight, the rigging, the swing path, the blind spot, the signals, the fall zone, and stop-work authority. Walk through the landing sequence and confirm everyone knows their role.
Key point: The failure here was not the radio; it was the absence of a backup communication method and a fall-zone plan. Fix both before the next lift.