Minnesota Boiler License Practice Exam

What is the maximum over MAWP that a safety valve is allowed to release?

1. No more than 3 percent above

2. No more than 6 percent above

3. No more than the MAWP

4. Equal to the MAWP

The correct answer is: No more than 6 percent above

The maximum allowable overpressure that a safety valve can release is established to ensure safe operation and protect equipment from potential damage. The safety valve is designed to open at a specified pressure, known as the Maximum Allowable Working Pressure (MAWP), and the allowable overpressure is typically set at no more than 6 percent above this limit. This 6 percent margin provides a safety buffer to account for fluctuations in pressure that may occur during normal operation. The rationale behind this regulation is to prevent excessive pressure build-up that could lead to equipment failure or catastrophic events. By limiting the release to a maximum of 6 percent above the MAWP, the safety valve effectively helps maintain system integrity while ensuring that there is a minimal risk of operating outside of the designed pressure limits. This standard is recognized in various codes and regulations governing boiler and pressure vessel safety.