Uniform Plumbing Code Practice Test 2026 - Free Plumbing Code Practice Questions and Study Guide

The maximum water supply pressure allowed by the Uniform Plumbing Code (UPC) without the need for pressure-reducing valves is set at 80 psi. This standard is established to ensure the safety and functionality of plumbing systems. At pressures above this threshold, there is an increased risk of damage to plumbing fixtures and fittings, and potentially compromises the integrity of the piping system. Excessive pressure can lead to leaks, bursts, and also affect the proper functioning of appliances, such as faucets and toilets, which are designed to operate optimally within certain pressure limits. By maintaining the maximum allowable pressure at 80 psi, the UPC aims to protect both the plumbing infrastructure and the health and safety of the building occupants.