Class 5 Boiler Practice Exam

What is the minimum hydrostatic test pressure an assembled boiler must withstand?

1. 30 psig

2. 45 psig

3. 60 psig

4. 75 psig

The correct answer is: 45 psig

The minimum hydrostatic test pressure for an assembled boiler is determined based on safety standards to ensure the integrity and reliability of the boiler system. The boiler must generally withstand a test pressure that is typically one and a half times the maximum allowable working pressure (MAWP) of the boiler or a specified minimum, whichever is greater. In many boiler regulations, including those from ASME and other safety codes, this minimum test pressure is often set at 45 psig. This value ensures that any potential weaknesses or faults in the boiler's construction are revealed before the boiler is put into service. It is essential for ensuring that the boiler components can handle pressures well beyond their normal operational limits, thereby promoting safety and preventing failures during operation. The other values do not meet the standard requirements for hydrostatic testing across most boiler codes. While pressures higher than 45 psig may serve specific cases or types of boilers, the regulatory minimum for hydrostatic testing in general practice is accepted to be 45 psig. This baseline is critical in maintaining consistent safety measures across boiler operations.