According to plumbing code, where are cleanouts on a trap prohibited?

Cleanouts on a trap are prohibited in shower and bathtub traps primarily due to the design and function of these fixtures. Showers and bathtubs often have unique drain configurations and materials that might not accommodate a cleanout without risking leaks or structural issues. The plumbing code emphasizes maintaining the integrity of the drainage system while ensuring it remains accessible for maintenance.

In the case of kitchen sink traps, laundry drain traps, and floor drain traps, cleanouts may be allowed because these areas typically experience different levels of use and potential clogs, and their designs can more readily integrate cleanouts for easier access to the drainage system. Overall, the prohibition in shower and bathtub traps aligns with best practices for plumbing installations, promoting reliability and minimizing maintenance challenges.