Master Plumber Practice Exam

When determining which type of fixture allows for the omission of cleanouts on horizontal drain lines that are less than 5 feet, it's important to consider plumbing codes and best practices. In most plumbing systems, sinks are generally permitted to omit cleanouts in specific scenarios. This can occur because sinks typically have a trap that aids in draining and can prevent clogs near the fixture itself. For horizontal runs of drain lines that are relatively short, there may not be a high risk of blockages that would necessitate additional cleanouts, especially provided the installation follows proper guidelines regarding slope and venting. However, specific cases may still require cleanouts based on local codes, which could involve unusual plumbing fixtures or configurations. Other fixtures like bathtubs, water closets, and showers often have different requirements for cleanouts, as they may encounter blockages more frequently due to their design and the nature of waste they handle. Therefore, the plumbing code makes specific allowances for sinks, making it feasible to omit cleanouts under the appropriate conditions.