Massachusetts Plumbers Journeyman Practice Exam

What is the requirement for hangers and supports for hubless cast iron soil piping for each change of direction?

1. One hanger for every two feet

2. One hanger for every three feet

3. One hanger for every four feet

4. One hanger for every five feet

The correct answer is: One hanger for every three feet

The requirement for hangers and supports for hubless cast iron soil piping is crucial for maintaining the integrity and stability of the piping system. The correct answer, which specifies one hanger for every three feet, is based on plumbing code regulations that ensure the piping is securely supported to prevent sagging and movement that could lead to leaks or failures. This specific spacing requirement of three feet allows for adequate support to handle both the weight of the piping and any potential external loads that may be applied during usage or maintenance. Proper support is essential especially at points where the direction of the pipe changes, as these are areas where stress can accumulate. In contrast, options proposing shorter or longer distances between hangers would not adequately assure the structural reliability of the piping. Having too few hangers can lead to excessive bending or shifting, while having too many can be unnecessary and complicate installation without providing additional benefit. Thus, the three-foot requirement strikes a balance between support and practicality in installation.