Which safety measure ensures that energy cannot be accidentally released from hydraulic systems during maintenance?

• A. Wheel chocks
• B. Wear PPE
• C. Follow lockout/tagout procedures
• D. De-energize hydraulics

Answer: (D)

Energized and pressurized hydraulic systems pose the immediate risk of fluid release or unexpected actuation, so the safest maintenance step is to de-energize the hydraulics. Turning off the hydraulic power source and relieving any stored pressure removes the energy that could drive motion or fluid out of a line. With the system depressurized and isolated, valves won’t suddenly open or pumps won’t restart, making it safe for technicians to work.

Wheel chocks are about preventing aircraft movement, not stopping hydraulic energy release. Wearing PPE reduces injury risk but doesn’t stop energy from being released if a line or component shifts or a valve is actuated. Lockout/tagout procedures provide the formal process to isolate and control energy sources and prevent re-energization, but the direct action that guarantees there’s no hydraulic energy available is de-energizing the hydraulics themselves and venting stored pressure.