Two-Way Radio Failure During a Blind Lift
You are the crane operator on a non-slewing mobile crane lifting a prefabricated air-handling unit, 1.9 t, onto a roof plant deck. The dogger is on the deck, out of your direct sight, and communication is by two-way radio on a shared site channel. The lift plan specifies radio communication with hand signals as backup. Halfway through the lift, the radio crackles and you hear only fragments; the dogger's last clear message was 'take it up slowly'. The load is about 4 m above ground and 9 m from the crane, and a worker is walking past the exclusion zone. The roof deck edge is close to the load's landing point.
1. What is the immediate action, and how do you decide whether to continue?
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Stop the lift in a controlled way. Hold the load stationary, keep it under control, and do not make further movements until communication is re-established. A partial radio message is not a signal; acting on a guess risks striking the deck edge or the worker. I would sound the horn or use the agreed emergency signal to alert the dogger and people nearby, and have the worker clear the exclusion zone.
The decision to continue depends on restoring reliable communication. If hand signals are viable and the dogger can move into my line of sight, I can resume under the signal system in the lift plan. If not, I would lower the load to a safe position and suspend the lift. I would not rely on a third party relaying messages, because relayed directions lose precision and add delay. The lift resumes only when I have a clear, unambiguous channel or a direct view of the dogger.
2. What should have been in place to reduce this risk, and what do you record afterwards?
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Before the lift: a dedicated radio channel or a check that the shared channel would not be congested; a radio check at the start of the shift; spare batteries or a backup radio; an agreed set of hand signals understood by both parties; a pre-lift briefing covering loss of communication; and a clearly marked exclusion zone with someone controlling entry. The dogger should also have had a position from which the load and the landing point were visible, or a second dogger placed to give a clear view.
After the event I would record the radio failure, the time, the load position when communication was lost, the action taken, and how communication was restored. I would report the defect in the communication equipment through the site's defect process, tag the faulty radio, and not resume lifting until it is replaced or repaired. I would also note the incursion into the exclusion zone so the site can review barricading and briefing.