What does the National Plumbing Code say about the installation of dishwashers?

The National Plumbing Code specifies that dishwashers must be installed with a dedicated drain and an air gap to ensure proper drainage and prevent contamination of the potable water supply. A dedicated drain allows for the efficient disposal of wastewater generated by the dishwasher, while the air gap serves as a safeguard against backflow, ensuring that any dirty water does not siphon back into the dishwasher and contaminate the clean water. This setup is essential for maintaining health and safety standards in plumbing installations.

While some alternatives suggest differing installation practices, having a dedicated drain and air gap is a critical requirement for compliance with plumbing codes and for protecting public health. Other options may not provide the same level of safety and efficiency, ultimately leading to potential plumbing issues or health hazards.