Summary
A small air leak in the left front wheel rim of a log stacker was scheduled for repairs. A mechanic deflated the tire and welded the rim to stop the leak. About 50 minutes later, while the tire was inflating, the tire exploded, inflicting fatal injuries.

Conclusions

Findings as to causes

• The tire exploded and a flap of the tire forced the worker's head into the rim, causing fatal head injuries.
• The tire was not removed before welding was done on the rim.
• The employer's work procedures that prohibit welding on mounted tires were not adequately communicated and were not followed.
• The supervisor did not have an adequate understanding of the employer's work procedures.
• A remote air chuck that would have kept the worker out of the line of trajectory was not provided or was not used.

• Management and workers accepted an unsafe act of welding on mounted wheels as "industry practice."
• Workers' and supervisors' understanding of the safe work procedures was not measured and confirmed.
• Manufacturer's instructions regarding welding on rims were not clear and led the employer to believe that small welding on rims with mounted tires was acceptable.
• The front left wheel on the log stacker had failed repeatedly due to a manufacturing defect and/or procedural misuse of the machine.

Links:
Hazard alert
Slide show