What is the maximum length of a trap arm as dictated by the UPC?

The maximum length of a trap arm is essential for maintaining proper drainage and preventing issues such as siphoning or blockage. According to the Uniform Plumbing Code, a trap arm connects the trap to the drainage system, and its length is prescribed based on the diameter of the pipe to ensure optimal performance and function.

For a 1.5-inch trap arm, the maximum allowed length is indeed 5 feet. This limit ensures that wastewater can flow efficiently while minimizing the risk of clogs or the loss of the water seal within the trap. If the trap arm were to exceed this length, it could lead to a scenario where the water seal is compromised, allowing sewer gases to enter the living space.

The specifications for other trap arm sizes provide clear guidelines as to their maximum lengths, which can vary. This is critical knowledge for plumbing professionals to ensure compliance with the code and to effectively design plumbing systems that operate safely and efficiently. By adhering to these standards, plumbers can prevent potential plumbing issues and ensure a high-quality installation.