An articulated hauler operator is descending a long, steep grade. The engine retarder is engaged, but the truck's speed is still increasing beyond the safe limit. What is the most appropriate next action?

Question: An articulated hauler operator is descending a long, steep grade. The engine retarder is engaged, but the truck's speed is still increasing beyond the safe limit. What is the most appropriate next action?

Answer options:

• Shift to a higher gear to reduce engine RPM and stress. ✅ Apply the service brakes intermittently and firmly to bring speed within control, then re-evaluate gear selection.
• Turn off the engine retarder to prevent over-revving.
• Engage the differential lock for better traction.

Correct answer: Apply the service brakes intermittently and firmly to bring speed within control, then re-evaluate gear selection.

Explanation: If the retarder alone cannot control speed, the operator must use intermittent, firm applications of the service brakes ('snub braking') to reduce speed to a safe level, then select a lower gear, as per CCOHS safe operating procedures.