American Society of Mechanical Engineers (ASME) Practice Exam 2026 - Free ASME Practice Questions and Study Guide

The first step after removing or gaging the safety valves is to fill the boiler with clean treated water. This step is crucial because hydrostatic testing is designed to verify the integrity and strength of the boiler or pressure vessel under pressure.

Filling the boiler with water ensures that it is completely filled and free from air pockets, which can influence the accuracy of the pressure readings and potentially lead to misinterpretation of the results. The use of clean treated water helps prevent contamination, corrosion, or scaling within the boiler, which can compromise its integrity over time.

Once the boiler is filled, it allows for an accurate assessment of the vessel's capability to withstand the specified test pressure without any leaks or structural failure. The other options, while relevant to the overall hydrostatic testing process, occur subsequent to this initial step. For instance, closing the vent is typically done after the boiler is filled, while increasing the pressure immediately would not be advisable without first ensuring that the system is properly filled and secure. A visual inspection is also important but should be conducted after filling to assess any conditions that may need to be addressed before proceeding with the pressure tests.