What is the minimum clearance required for a cleanout in a horizontal waste pipe?

The minimum clearance required for a cleanout in a horizontal waste pipe is 12 inches. This requirement ensures adequate space for maintenance and servicing of the plumbing system. Sufficient clearance allows access for removing the cleanout plug without obstruction, which is essential for effective cleaning and inspection of the waste line. It also helps prevent any potential damage to the surrounding areas when dealing with clogs or performing repairs. Having a standard clearance of 12 inches not only promotes safety during maintenance tasks but also aligns with industry best practices to facilitate efficient plumbing operations.