724.2 Toilet soil lines shall be separated from house drainage — 2025 California Plumbing Code

lines to a point outside the building unless an automatic back- water check valve is installed to prevent backflow. Drainage from toilet bowls and urinals shall not be discharged into a grease catch basin, nor shall such drainage be permitted to enter the sewer lines at a point where there might be a possi- bility of such drainage backing up and flooding the floor of the building.