In plumbing codes, what generally governs the dimensions and fittings used?

Building codes generally govern the dimensions and fittings used in plumbing installations because they establish standards for construction and ensure safety, health, and accessibility in buildings. Building codes include specific requirements for the types of materials, sizes of pipes, fittings, and installation practices that must be followed to comply with local laws and regulations.

These codes are enforced by government entities and are designed to protect public welfare by ensuring that plumbing systems are safe, efficient, and reliable. They are developed based on national standards and adapt to local needs, often incorporating guidelines from various plumbing associations and manufacturer instructions as references but ultimately are framed in the context of the broader legal and safety framework that building codes provide.

While manufacturer instructions are important for the proper installation of specific products, they must align with the overall requirements set forth in the building codes for compliance. Health codes primarily focus on sanitation and public health aspects but do not specifically encompass the technical specifications for fittings and dimensions used in plumbing. Plumbing associations may provide guidance and best practices but do not have the same legal standing as building codes.