The wheels on the bus go round and round, but will they fall off?
OSHA requires employers to protect workers who service wheel and rim components, mount or dismount wheels, inflate or deflate tires, and inspect wheels and rims. Workers face serious hazards when servicing large vehicles such as trucks, tractors, trailers, buses, and off-road machines. But once the servicing is done, there’s still risk if wheels and rims aren’t carefully inspected.
Post-service wheel and rim inspections
Wheels and rims are continually subjected to heavy loads and forces that can fatigue assemblies and materials. Fatigue can lead to cracking and if not found early, could result in a catastrophic failure with the potential for serious injury to anyone nearby.
Inspections should be performed by the original manufacturer of the wheel and rim assembly, their agent, or a competent person. Inspections should occur at regular intervals, taking into consideration environmental conditions, use, and previous maintenance or servicing.
A proper inspection requires:
- Prepare wheel and rim surfaces by cleaning them of foreign materials that may interfere with the inspection.
- Include all components of both wheel and rim assemblies to ensure a thorough inspection.
- Lock rings – visually inspect for wear, deformation, corrosion, or insufficient overlap.
- Flanges – visually inspect for wear, cracking, corrosion, deformation, or damage.
- Bead seat bands – visually inspect for wear, cracking, corrosion, and sufficient contact with the lock ring, flange, etc.
- Rim bases – visually inspect for wear, cracking, corrosion, or damage to the rim face, rim base, valve, and wheel assembly disc. Magnetic and ultrasonic testing should also be considered to locate potential defects.
- Tires – visually insect tread, side walls, and bead for wear, cracking, deformation, or damage.
- Document inspection findings and implement remediations to correct issues. Defects should be clearly identified to include length and depth of irregularities, as well as noting service life. Serious or recurring defects should be investigated further to determine a root cause.
Keys to remember
Wheel and rim servicing is extremely dangerous. But safety doesn’t stop with the service. Thorough inspections are vital for ensuring catastrophic failures are prevented. You want the wheels to go around, not fall off!