Mall Escalator With Broken Comb Teeth and a Loose Stop Button
You are performing the annual inspection on a 1994 mall escalator that runs 14 hours a day. At the lower landing you find two missing comb teeth and a crack at the left corner of the comb plate. At the same location, the step-to-skirt clearance looks wider than at adjacent steps. The lower emergency stop button works, but the upper stop button is loose and takes two pushes to stop the escalator. The mall's maintenance log shows the last recorded comb-plate inspection was 11 months ago, although housekeeping has been wiping the balustrades daily. The escalator is running and shoppers are using it. The mall manager says the missing teeth have been like that for months and asks you to finish the inspection and write it up after the mall closes.
1. What immediate action is required, and can the escalator remain in operation?
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Stop the escalator and remove it from service. Missing comb teeth, a cracked comb plate, abnormal step-to-skirt clearance, and an unreliable upper stop button are passenger-safety defects. Barricade both landings and follow lockout/tagout. Notify the mall manager in writing that the unit is out of service and must not be restarted for shopper use. Do not wait until closing to act, because a passenger could catch clothing or a shoe at the comb plate or be unable to stop the unit from the upper landing. Record the conditions with measurements and photos before any repair.
2. What inspection and repair scope should you require before considering return to service?
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Replace the damaged comb plate with the manufacturer's parts and verify proper comb-to-step clearance. Inspect the steps, skirt panels, and step demarcations in that area, not just the damaged comb teeth. Check the skirt panel clearance against the adopted A17.1 requirements and repair any wider gap. Repair or replace the upper stop button so one push reliably stops the escalator. Verify the comb-plate safety device and related switches operate. Because the log shows a long gap in comb-plate inspection, inspect the full unit rather than treating this as a cosmetic repair.
3. What testing and documentation should be completed before the escalator carries passengers again?
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After repairs, run the escalator empty through several complete cycles and check for binding, unusual noise, and proper step-to-comb engagement. Test both emergency stop buttons and confirm they stop the unit as required. Re-measure the step-to-skirt clearance and document the readings. Update the maintenance log with the defects found, repairs made, parts installed, and test results. Notify the AHJ if the condition requires reporting or reinspection. Release the unit only when the repairs and tests are complete and the barricades can be removed safely.