Massachusetts Plumbers Journeyman Practice Exam

When conducting a deflection test on hubless cast iron soil pipe, what is the minimum required deflection per lineal foot?

1. 1/2"

2. 3/4"

3. 1"

4. 1 1/4"

The correct answer is: 1"

The correct deflection amount for hubless cast iron soil pipe during a deflection test is indeed measured at a minimum of 1 inch per lineal foot. This standard is crucial to ensure the pipe can accommodate typical loads and stresses that it may encounter during its lifespan without significant deformation or compromise to the plumbing system's integrity. Deflection testing is an important quality control measure that helps to ensure that the installed pipe remains functional under pressure and during environmental changes. A minimum of 1 inch of deflection indicates that the pipe has sufficient flexibility to handle both thermal expansion and contraction as well as potential ground movement without risk of failure or leakages. Other options reflect lesser amounts of deflection, which would not meet the necessary performance criteria for this type of plumbing installation. Proper adherence to these standards ensures longevity and reliability in plumbing systems.