A ___________ is a lock that holds an energy isolating device in a safe position.

• A. Lockout
• B. Lockout device
• C. Tagout
• D. Interlock

Answer: (B)

The main idea is understanding the equipment used to physically secure energy sources during maintenance. A lockout device is the actual lock placed on an energy isolating device (like a switch or valve) to hold it in a safe position and prevent energization. This ensures the machinery can’t be started accidentally while work is being done, as only the authorized person with the matching key or release can remove it. This is different from the broader term lockout, which refers to the overall procedure of isolating energy; tagout relies on tags to communicate the isolation without providing physical locking, and an interlock is a device that prevents operation under certain conditions but isn’t the locking device used to hold an isolating device in a safe position.