Master Plumber Practice Exam

Asbestos cement piping is the correct answer because it contains asbestos, a material known for its strength and durability but also for its potential health risks when fibers are released into the air. The disturbance or degradation of asbestos-containing materials can lead to the release of these harmful fibers, which increases the risk of airborne exposure. Therefore, regulations and best practices dictate that asbestos cement piping should not be installed under or within a close proximity of buildings to minimize any health risks associated with asbestos exposure, as well as to avoid future complications related to maintenance or renovations.

In contrast, the other materials mentioned—ABS, cast iron, and copper—do not pose the same health hazards associated with asbestos. These materials can be safely installed in various locations, including under buildings, provided that they comply with local building codes and regulations. Each of these materials has its own application strengths within plumbing systems, but they do not carry the same restrictions related to health risks as asbestos cement does.