Piping must be supported at distances not exceeding the spacing specified in which of the following?

The correct answer is based on Table 305.4, which is a critical reference in the North Carolina Mechanical Code that provides specific guidelines on the maximum allowable spacing for supporting piping. The table outlines these distances based on factors such as the type of piping material, the diameter of the pipe, and the application, ensuring that pipes are adequately supported throughout their length. This is essential to prevent sagging, which can lead to stress, leaks, or failures.

While installation guidelines and building code requirements may touch on related concepts, they do not specifically dictate the precise spacing for pipe supports as outlined in Table 305.4. Similarly, while "Pipe Support Regulations" might suggest a regulatory context, it does not directly reference the established numeric standards that Table 305.4 provides. Therefore, using Table 305.4 is crucial for compliance with safety and performance standards in mechanical installations.