Blind Pick With Hand Signals and a Restricted Swing
You are setting a 6,000 lb pipe spool onto a pipe rack inside a congested process area. The operator cannot see the landing zone; a rigger with a radio is positioned there, but a second worker is also giving hand signals from a different location. The swing path passes within 4 ft of an energized overhead line (the utility says it is 13.8 kV, not de-energized) and over a walkway where workers are passing. Wind is light. The rigger on the radio reports the spool is 'about a foot high' but the load line is drifting. The operator hears two different commands at once.
1. How do you establish one clear line of communication and control the swing?
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Stop the lift until command is unambiguous. Only one person - the designated signalperson - gives signals, and only the operator takes signals from that person (plus a stop signal from anyone). The second worker giving hand signals must be told to stop; if hand signals and radio conflict, the operator stops.
Agree on the signal method before resuming: radio with a dedicated channel, hand signals as backup only if the signalperson is in clear view. Confirm radio battery and clarity. Use a pre-lift briefing that covers the path, the stop point, the tag line handlers, and who calls 'stop.'
For the drift: the load line drifting with light wind suggests the spool is not balanced or a tag line is being pulled unevenly. Have tag line handlers steady it and confirm the spool's center of gravity is under the hook before continuing. Do not chase a drifting load with swing; correct with the hoist and tag lines.
2. What is your plan for the 4 ft proximity to the 13.8 kV line and the walkway?
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Treat the line as energized. Minimum approach distances for cranes to energized lines are set by the utility/OSHA table and depend on voltage; for 13.8 kV the required clearance is well beyond 4 ft (typically on the order of 10 ft for high-voltage lines under the OSHA crane standard, and greater if the utility requires). Four feet is not acceptable under any interpretation.
Options, in order of preference:
- Have the utility de-energize and visibly ground the line, with confirmation in writing, then proceed.
- Establish a physical barrier/limit (marked boundary, spotter, or mechanical stop) that prevents any part of the crane, load, or rigging from entering the minimum approach distance, and reroute the swing so the load never passes near the line.
- If neither is possible, the lift does not proceed.
For the walkway: barricade it and stop pedestrian traffic for the duration of the swing, or reroute the path. A spotter at the walkway is not sufficient if workers can walk under a suspended load. Confirm the barricade is in place before the swing begins and that the signalperson can see the barricade.