Massachusetts Plumbers Journeyman Practice Exam 2025 – All-in-One Guide to Master Your Licensing Test!

The minimum pipe diameter for the chamber vent of an outside grease interceptor is 4 inches. This is to ensure that there is adequate airflow to prevent the buildup of harmful gases and to maintain proper functioning of the interceptor. A larger diameter helps to facilitate better ventilation, allowing for the escape of gases that may accumulate in the system and preventing potential pressure buildup which could lead to malfunctions or hazards.

In grease interceptors, maintaining proper venting is crucial for efficient operation, as it helps to ensure that the interceptor functions effectively without blockage or buildup. Insufficient venting can lead to issues such as odor problems, reduced efficiency in grease removal, and potential failure of the system. Therefore, a minimum diameter of 4 inches is established to assure sufficient venting for these systems.