Rhode Island Journeyman Plumber Practice Exam

What issue does venting a sink address?

1. Air pressure changes

2. Siphonage

3. Pipes freezing

4. Excess noise from drainage

The correct answer is: Siphonage

Venting a sink primarily addresses the issue of siphonage, which occurs when water is drawn out of P-traps in plumbing systems, allowing harmful gases and odors from the sewer to enter the living space. Proper venting establishes an air path that equalizes the pressure within the drainage system as water flows, preventing a vacuum from forming that could lead to the siphon effect. This means that venting plays a crucial role in maintaining trap seals, ensuring that wastewater can flow freely while simultaneously preventing sewer gases from escaping into the home. While air pressure changes are a factor that venting helps to mitigate, the specific focus on siphonage highlights the importance of maintaining a consistent water seal in the traps. Other potential issues like pipes freezing or excess noise from drainage do not directly correlate with the primary function of sink venting, as they are addressed by different plumbing practices or systems.