Can water pipes be used in place of rigid conduit?

Using water pipes in place of rigid conduit is generally not acceptable unless they meet specific conditions, typically related to size and application. When the size of water pipes is sufficient to accommodate the necessary electrical conductors while also providing adequate protection from physical damage, they may be permissible. This situation usually arises if the other requirements of the electrical code, such as insulation and grounding, are also met.

It's important to note that the primary function of rigid conduit is to protect electrical wiring and to provide a reliable pathway for electrical circuits. Water pipes, however, are primarily designed for transporting water and may not have the necessary structural integrity or protective features required for electrical installations. Therefore, while there can be specific scenarios where water pipes could potentially be used, it requires careful consideration of their size and capabilities to ensure they can safely house electrical conductors.

The other options imply broader allowances or restrictions that do not align with standard electrical practices. In summary, the correct answer emphasizes the importance of size and compliance with safety standards when considering alternative materials for electrical conduit.