Question 7 of 7: Accident Case Analysis — Millwright Ladder Fall

Question 7: Accident Case Analysis — Millwright Ladder Fall (20 marks: 7/7/6)

Question text not reproduced: the examination questions are © Engineers and Geoscientists BC. Open the official past paper (linked at the top of this page) to read the question, then follow the worked solution below.

(i) Cause of the Accident

• Immediate cause — the millwright overreached from a ladder (lost balance) while adjusting the flywheel chain in place, and fell onto the shaft, then the conveyor, then the floor.
• Root/contributing causes (multiple-factor):
  • Machine not locked out — the adjustment was attempted with the press still set up to run, rather than shut down, de-energized and locked out. (The paper does not say the press was running; the $5,000 of damage to the shaft and belts is consistent with stored or live energy in the drive, and in any case the flywheel, chain and shaft are hazardous energy that lockout/tagout exists to isolate before any adjustment. State the assumption, as the exam's own instruction 1 invites.)
  • Improper access/work platform — using a ladder for a task requiring reach and both hands; overreaching beyond safe limits; no stable work platform/scaffold and no fall protection at height.
  • Procedure/training — no safe procedure for the adjustment; inadequate training/supervision.
  • Guarding — exposed shaft/moving parts and conveyor in the fall path (the broken conveyor guard suggests guarding issues).

(ii) Corrective Actions

• Lockout/tagout — require the press to be shut down, de-energized and locked out (moving parts stopped) before any adjustment.
• Proper access — provide a stable work platform/scaffold or properly positioned/secured ladder; prohibit overreaching (keep the body within the ladder side rails); use fall protection where required at height.
• Safe procedure and training — written procedure for the adjustment; train and supervise; two-hand/secure footing.
• Guarding — ensure shafts, flywheel, chain and conveyor are properly guarded.

(iii) Follow-Up Actions

• Investigate and document (root-cause analysis); report as legally required.
• Implement corrective actions; write/update the safe-work and LOTO procedures.
• Retrain millwrights/maintenance staff; verify LOTO use, access equipment and guarding through inspection/audit.
• Inspect similar maintenance tasks plant-wide for the same risk; repair the damaged equipment/guards; monitor for recurrence; support the injured worker and share lessons learned.