Master Plumber Practice Exam

Which material is most often used for pressure piping in plumbing?

1. PVC

2. Cast iron

3. HDPE

4. CPVC

The correct answer is: PVC

The most commonly used material for pressure piping in plumbing is PVC (Polyvinyl Chloride). PVC is favored for several reasons, including its excellent resistance to corrosion, lightweight nature, and ease of installation. It is also non-toxic and has a smooth interior that reduces friction, enhancing flow rates. The ability to be molded into various shapes and sizes makes PVC versatile for a wide range of plumbing applications. Additionally, PVC can withstand various temperatures and pressures, making it suitable for both residential and commercial plumbing systems. While other materials like cast iron, HDPE, and CPVC are also used in plumbing, they typically serve more specialized functions. Cast iron is often used for drainage and sewer applications due to its robust nature and noise dampening characteristics. HDPE (High-Density Polyethylene) is used chiefly in underground applications and is prized for its flexibility and resistance to impacts. CPVC (Chlorinated Polyvinyl Chloride) is suitable for hot water applications but is generally less popular than PVC for standard pressure piping systems. Thus, PVC stands out as the most prevalent choice for pressure piping in typical plumbing installations.