Rhode Island Journeyman Plumber Practice Exam

When should a water hammer arrestor be used?

1. When using low-pressure systems

2. When accessible

3. In all installations

4. Only for large diameter pipes

The correct answer is: When accessible

A water hammer arrestor should be used when it is accessible, making option B the correct choice. Water hammer occurs when a fluid in motion is forced to stop or change direction suddenly, leading to a pressure surge in the pipes. This phenomenon can cause noise and potentially damage plumbing systems. Water hammer arrestors are designed to absorb these shock waves, mitigating the effects and protecting the integrity of the plumbing system. While it’s crucial for the installation of these devices to be straightforward for maintenance purposes, accessibility ensures that they can be effectively installed and serviced when necessary. Using water hammer arrestors in all installations might not be practical or necessary; the need for them can vary based on the specific circumstances of the plumbing system. Low-pressure systems may experience water hammer differently, and although larger diameter pipes can produce stronger impacts, the use of arrestors primarily hinges on the likelihood of water hammer occurring rather than the size of the pipes alone.