Minnesota Boiler License Practice Exam 2025 – All-in-One Guide to Passing with Confidence

The preferable pressure reading on steam gauges is typically set to 150%. This setting is important because it provides a margin of safety above the operating pressure of the system. Steam systems are often designed to operate at a certain pressure, and having a gauge that can read up to 150% of that operating pressure allows operators to monitor for any overpressure situations that could become unsafe. This buffer helps in identifying malfunctioning equipment or system problems before they lead to hazardous conditions.

For instance, if a boiler is intended to operate at 100 psi, a gauge that reads up to 150 psi not only shows what’s normal but also alerts operators if the pressure begins to approach dangerous levels. This ensures greater safety and facilitates timely intervention.

In contrast, gauges set to higher readings, such as 200% or 250%, may lead to delays in recognizing dangerously high pressures due to the larger buffer they offer. A reading of 100% is typically inadequate in terms of safety margin for most applications. Thus, the 150% reading combines safety with practicality, making it the most sensible choice for steam gauge pressure readings.