What potential issue does the UPC aim to prevent regarding hazardous materials and plumbing systems?

The Uniform Plumbing Code (UPC) is designed to ensure the safety and integrity of plumbing systems. One of its primary objectives is the prevention of water contamination. This is critical because plumbing systems often carry potable (drinking) water, and any hazardous materials entering these systems can pose serious health risks to consumers.

The UPC establishes regulations and standards that help to prevent cross-connections, which occur when non-potable water or contaminants can potentially mix with the potable water supply. This is key to safeguarding public health, as contaminated drinking water can lead to various waterborne diseases and health complications. By enforcing guidelines for backflow prevention and proper system design, the UPC aims to mitigate the risk of water contamination in plumbing systems.

The other options, while important in plumbing considerations, do not directly relate to the specific aim of preventing hazardous materials from contaminating water supplies. Overheating of pipes, blockage in drainage, and excessive pressure buildup are all concerns that affect the performance and safety of plumbing systems but do not address the critical issue of maintaining clean and safe drinking water.