ELEVATOR INCIDENT

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A maintenance worker was sent to replace the astragals (seals) on the hoistway doors of a hydraulic industrial elevator. The hoistway doors (the doors at each floor level) were constructed of two halves: a top and a bottom. The hoistway doors opened such that the top went vertically up, while the bottom went vertically down. While the maintenance worker was at the middle floor of three floors with the hoistway door partially open, someone from the lower floor pressed the button to call for the elevator car. The elevator car came down striking the maintenance worker’s head, resulting in a near decapitation.

Steps Taken:

  • The expert conducted a site inspection of the factory floor level, the elevator hoistway, the elevator car, and the elevator machine/control room.
  • He conducted tests of the elevator, including riding the elevator to each floor and documenting all car and hoistway interlocks.
  • He inspected a hoistway door interlock that had been removed and replaced after the accident.
  • He reviewed the drawing and plans of the original construction of the elevator as well as the current drawings and schematics of the elevator.
  • He reviewed ANSI A17.1 Safety Code for Elevator and Escalators.
  • He reviewed the maintenance contract and maintenance history for the elevator.
  • He reviewed the availability of parts for the elevator as the elevator was in excess of 30 years old.
  • He reviewed the maintenance employee’s background, education, and experience.

Final Findings:

The maintenance worker was not trained or certified and had no experience in elevator repair or maintenance.  Due to a lull in workload, the maintenance worker was sent to perform the astragal repair, even though the factory had an inspection and maintenance company on contract.  Although familiar with the concept of lockout/tagout, the maintenance worker did not de-energize and lockout the controls and power source to the entire elevator in the elevator machine room.  The maintenance worker was relying on the hoistway door interlock to disable the elevator.  Unfortunately, the door interlock had been broken at some point in time and weld-repaired without fixture, constraint, or any kind of dimensional check or control.  The door interlock was so out of tolerance that it was no longer functional.

The inspection and maintenance company had approved the elevator for use year after year despite the fact that warning lights and an audible alarm at each floor had been disabled.  ANSI A17.1 may not require an elevator to be updated to the latest safety devices, but ANSI A17.1 does not allow a reduction in kind and quality of the safeties originally designed for the elevator. The human factor causative to the incident was that hydraulic elevators make very little noise as compared to electric elevators, and the machines in the factory were very loud.  Without the floor lights and audible alarm to indicate that the elevator car was in motion and operational, the maintenance worker had no warning.