During maintenance, which action is important regarding valves connected to a pressure source?

Including valves in the lockout/tagout process is crucial during maintenance as it ensures safety by preventing accidental activation of equipment or systems that could lead to serious injuries. The lockout/tagout procedure is designed to keep workers safe when they are performing maintenance or servicing on machinery or systems that might release energy unexpectedly, which includes pressurized systems. By locking out or tagging these valves, you ensure that they cannot be operated until the maintenance work is completed and the lockout/tagout measures are safely removed.

This step is essential because valves connected to a pressure source can pose significant hazards if they are inadvertently operated during maintenance. By prioritizing this action, maintenance personnel can significantly reduce the risk of accidents, ensuring a controlled and safe working environment.

In contrast, while checking valves for leaks and ensuring good flow control are also important practices, they do not address the immediate safety concerns associated with maintenance activities in the same way that a lockout/tagout procedure does. Leaving all valves open is not advised as it could lead to unintended pressure release or accidents.