The prescribed portions of the standards referenced in the IPC and listed in Chapter 15 are considered _____.

The prescribed portions of the standards referenced in the International Plumbing Code (IPC) and listed in Chapter 15 are considered requirements because they establish mandatory criteria that must be followed in plumbing installations and practices. These requirements are designed to ensure safety, functionality, and compliance with legal standards. Adhering to these requirements is crucial for anyone involved in plumbing work, as they form the foundation of acceptable plumbing practices and help avoid violations that could lead to problems or hazards.

In contrast, guidelines refer to recommendations that may suggest best practices but are not enforced as mandatory. Alternatives might imply other choices outside the prescribed standards, and modifications would indicate changes to existing codes rather than the established requirements. Thus, recognizing the prescribed portions as requirements highlights their authoritative nature in the context of plumbing standards.