Texas Compressed Natural Gas (CNG) Category 3 Practice Exam

When the seals on CNG pressure relief valves are broken, the integrity and reliability of the valve are compromised. These seals are critical for maintaining the pressure and ensuring that the valve functions correctly to relieve excess pressure safely. If the seals are damaged, there is a risk that the valve may not operate as intended during an overpressure situation, which could lead to dangerous conditions.

Removing the valve from service is essential because using a compromised valve can lead to catastrophic failures, including leaks or explosions. The safety of personnel and the equipment relies significantly on the proper operation of pressure relief devices. Therefore, a broken seal indicates that the valve no longer meets safety standards and must be taken out of service until it can be properly addressed, which may include repair or replacement. This ensures that any risks associated with pressure management in CNG systems are minimized, maintaining a safe operating environment.