Minnesota Boiler License Practice Exam 2026 – All-in-One Guide to Passing with Confidence

Two safety valves are required on boilers that have more than 500 square feet of heating surface to ensure adequate pressure control and safety. This requirement is established in boiler safety codes, which aim to prevent overpressure situations that could lead to catastrophic failures or explosions.

Having multiple safety valves allows for a backup system in case one valve fails. In larger boilers, the amount of energy and pressure involved increases significantly, which is why the threshold is set at 500 square feet. This ensures that there is sufficient redundancy and safety mechanisms in place to handle the potential hazards associated with larger heating surfaces.

In contrast, smaller boilers may not require the same level of safety because the risks associated with overpressure are considerably less. The specifics of these regulations are outlined by organizations such as the National Board of Boiler and Pressure Vessel Inspectors, which govern the safe operation of boilers across various jurisdictions.