Which code governs plumbing installations in most areas?

The International Plumbing Code (IPC) and the Uniform Plumbing Code (UPC) are widely adopted codes that establish minimum standards for plumbing installations. These codes provide essential guidelines on the design, installation, and maintenance of plumbing systems, ensuring safety, health, and welfare.

The IPC is recognized for its comprehensive approach and is used in many jurisdictions across the United States, promoting consistency and safety in plumbing practices. Meanwhile, the UPC, which is also prevalent, emphasizes similar principles and has been adopted in various regions as a reliable standard. Both codes are essential for inspectors, contractors, and municipalities to ensure that plumbing systems are safe, efficient, and compliant with modern standards.

In contrast, while local plumbing codes and state regulations can be important, they typically refer to adaptations or modifications of the national or international standards rather than being the primary governing documents. Therefore, B is the definitive answer as it reflects the codes that govern plumbing installations in most areas effectively.