Night Entrapment and a Warm Brake Drum
You are on call for a 12-storey apartment building with a single traction elevator. At 02:00, two passengers are trapped between floors 7 and 8; the car is about 1.2 m above the 7th floor. The superintendent has already used the emergency door key to open the hoistway door and talk to them, but did not move the car. You arrive, perform a manual rescue, and find no controller fault. After reset, the car runs normally on a test trip. The maintenance log shows the door operator was adjusted two days ago and the brake was “checked” last month. The superintendent wants you to put it back in service so the night shift can use it. You notice the car is leveling slowly and the brake drum is warm.
1. What must you do before deciding whether to return the car to service?
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A reset and a normal test trip are not enough. The car stopped uncommanded between floors, and a warm brake drum plus slow leveling suggests the brake may be dragging or the control is repeatedly correcting position. I would check the brake drum, lining, springs, adjustment, and release gap; check for oil or contamination on the lining; and observe whether the brake releases fully. I would review the door-operator adjustment made two days ago and check the door locks and zone position. I would run the car with rated load and watch leveling, stopping, and brake temperature. I would also check for fault logs and power problems. If I cannot identify a cause, the car stays out of service. The superintendent’s staffing need does not justify returning a car with an unexplained stop and a hot brake.
2. Is this entrapment reportable to TSSA?
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An entrapment with no injury is not automatically reportable in every case, but the answer depends on what caused it. If the investigation shows a brake failure, a door-lock failure, an uncontrolled movement, or another unsafe equipment condition, it should be reported under the TSSA reporting requirements. If it was a transient power interruption with no equipment defect, the maintenance record may be sufficient. I would not make that decision solely to avoid paperwork. I would document the time, car position, passengers, rescue method, reset result, brake temperature, and maintenance history. If there is any doubt about reportability, I would call TSSA and follow their direction. The owner should also receive a written record of the event and the car’s status.
3. What root-cause checks and follow-up would you document?
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I would document the brake inspection results, including drum condition, lining wear, spring condition, gap measurements, and whether the brake was dragging. I would record the door-operator adjustment and observe door lock engagement and car leveling over several trips. I would check the controller fault log and the machine-room temperature. A warm drum after a short run points to dragging or frequent releveling; slow leveling may point to a valve or control issue. I would interview the superintendent about what was seen and heard before the stop. Follow-up would include a loaded test, a brake-temperature check after repeated trips, and a review of the last maintenance records. If a defect is found, it must be corrected and the car retested before return. The record should state why the car was removed from service and what evidence supported its return.