Size of Waste Pipes
| Urinals................... | 2 inches |
| Kitchen sink........... | 2 inches |
| Slop sink................ | 3 inches |
| Receptacles............ | 11⁄2 inches |
| Bath tubs................ | 11⁄2 inches |
| Lavatories.............. | 11⁄2 or 11⁄4 inches |
| Wash trays............. | 2 inches |
Tell-tale Pipe.—The tell-tale pipe is a small pipe that extends from the trough, pan, or box that is under a line of pipe or fixtures to the open cellar. When water is seen running out of this pipe, it shows that a leak exists somewhere in the line of pipe that is in the box or trough. The use of this pipe saves the destruction of walls and ceilings.