Master Plumber Practice Exam

A fixture vent pipe increased one pipe size its entire length ____.

1. May exceed the maximum horizontal length limited by code

2. Will be a better workmanship job

3. Will increase the venting efficiency

4. Will reduce the cost of installation

The correct answer is: May exceed the maximum horizontal length limited by code

Increasing the size of a fixture vent pipe along its entire length can potentially impact its compliance with code regulations regarding maximum horizontal lengths. Plumbing codes, such as those from the International Plumbing Code (IPC), often specify guidelines for venting systems, including limitations on the horizontal run based on the size of the vent pipe. If the pipe size increases, it might exceed the code's maximum length guidelines, which are designed to ensure effective air circulation and minimize the potential for drainage system backups or siphoning. While improved workmanship, venting efficiency, and installation costs are important factors in plumbing, they do not directly relate to the implications of increasing a pipe size in this context. The primary concern revolves around ensuring that the venting system adheres to established codes to maintain functionality and safety in the plumbing system.