Installation of supply lines and fittings for all fixtures should prevent what issue?

The installation of supply lines and fittings for all fixtures is primarily aimed at preventing backflow. Backflow occurs when water flows in the opposite direction than intended, which can lead to contamination of water supply systems. Properly installed supply lines, along with appropriate backflow prevention devices, ensure that potable water remains uncontaminated by wastewater or pollutants that may enter the system.

Moreover, by adhering to correct plumbing practices and using the right materials and fittings, the risk of backflow is significantly reduced. This is critical not only for maintaining water quality but also for compliance with local plumbing codes and safety standards. Ensuring that supply lines create a one-way flow prevents situations where contaminants could inadvertently mix with clean water sources. Thus, proper installation is essential for safeguarding both public health and the integrity of the plumbing system.