Which condition would necessitate removing a tank from service?

Removing a tank from service is critical when safety could be compromised, and visible damage to the pressure relief valve is a clear indication of this. The pressure relief valve is a safety device designed to release excess pressure that can build up within the tank, preventing possible explosions or catastrophic failures. If there is visible damage, such as corrosion, cracks, or leaks, it may fail to operate correctly, leading to dangerous operational conditions. Therefore, ensuring the integrity of this component is essential for safe operations, warranting the removal of the tank from service.

While conditions like overfilling or rust on the tank's surface indicate potential issues, they may not immediately require removal from service if the tank's structural integrity is still intact and management procedures can address these concerns. Additionally, exceeding the expiration date suggests it may be time for inspection or maintenance, but does not inherently indicate that the tank should be removed from use without a thorough assessment. The critical need for safety in operations highlights the priority of addressing the pressure relief valve's condition as the foremost reason for withdrawal from service.