Cage Stuck Between 10/F and 11/F with a Dizzy Worker
At a 40-storey site in Sha Tin, the operator and two workers are descending in a builder's lift cage when it stops abruptly between 10/F and 11/F. The cage floor is about 1.2 m below the 11/F landing. The control panel is unresponsive, the emergency stop is not pressed, and the alarm bell works. The operator's mobile phone has signal. One worker says he feels dizzy and wants to climb out onto the 11/F landing. The site emergency contact does not answer. The hoist has a manual lowering device, but the operator has never used it on this model. The other hoist on the same mast is still running.
1. What are the operator's immediate priorities, and what should he prevent the workers from doing?
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The first priority is to keep everyone inside the cage and stop anyone from climbing out. The cage is 1.2 m below the landing, so a person climbing up would be exposed to a fall into the shaft and could be struck by the cage or counterweight. The operator should close and secure the cage gate, try the alarm and intercom, and use his mobile phone to call the site emergency number and, for the dizzy worker, 999. He should give the location, the number of persons, the worker's condition and the fact that the cage is stuck. He should not repeatedly reset the control or force the contactor; that can cause unexpected movement. He should switch off the control if it is safe to do so, but keep the emergency light and alarm available. He should also ask the site to stop the other hoist on the same mast so that it does not pass or create movement nearby. Keeping the cage still and the occupants calm is more important than a quick self-rescue.
2. How should the rescue be carried out, and what should the operator do about the manual lowering device?
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The rescue should be carried out by trained site rescue personnel or the hoist service provider, not by the operator improvising. The operator should tell the emergency contact that a manual lowering device is fitted but that he has not been trained on this model. He should not attempt to use it from memory while two workers are inside, because a mistake can release the brake uncontrolled or lower the cage onto the buffers. If a trained person attends and confirms the procedure, the area below should be cordoned off, the other hoist stopped, and communication maintained with the cage. The dizzy worker should be kept seated, not asked to climb. If the cage can be safely lowered to the ground or raised to a landing under trained control, that is preferable to a shaft evacuation. The operator should follow the trained person's instructions, keep the cage gate closed until the cage is level with a landing, and ensure the landing area is clear before anyone exits.
3. What should happen after everyone is out, and what records and notifications are needed?
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After evacuation, the hoist should remain out of service until the cause of the stoppage has been found and corrected. The operator should not reset the panel or run the hoist to 'test' it without authorisation. The area should be preserved so that the failed component, limit switch or control fault can be examined. The operator should record the time, position, symptoms, alarm and communication attempts, the names of the occupants and the rescue method. The incident should be reported to the employer, the site safety officer and the hoist owner. The dizzy worker should receive first aid or medical assessment, and the incident should be investigated. If the stoppage was a failure of the hoist or a dangerous occurrence, the site should consider the notification requirements under the Factories and Industrial Undertakings Ordinance. The hoist should be examined and tested before it returns to service, and the operator should be trained on the manual lowering device before being asked to use it.