Minnesota Boiler License Practice Exam

What is the maximum allowed pressure setting above the M.A.W.P. when additional valves are used?

1. 3%

2. 4%

3. 5%

4. 6%

The correct answer is: 3%

The maximum allowed pressure setting above the Maximum Allowable Working Pressure (M.A.W.P.) when additional safety valves are installed is typically set at 3%. This standard is established to ensure that the safety margins are maintained and that the pressure does not exceed safe operational limits. In the context of boiler operations, adhering to this 3% limit helps to protect against potential overpressure conditions that could lead to equipment failure or hazardous situations. Additional safety valves are installed to provide redundancy and further safeguard the system, allowing only a slight increase in pressure above the M.A.W.P. This approach promotes safety and reliability within the boiler system, making it a crucial guideline for boiler operators and engineers. In contrast, higher percentages such as 4%, 5%, or 6% would not conform to the safety requirements set forth in industry standards and could pose an increased risk of overpressuring the equipment, undermining the protective benefits of having additional safety valves.