A sanitary tee should be used when connecting a horizontal run, such as a waste arm to a vent stack or vertical riser.

What is the difference between a sanitary tee and a regular tee?

A sanitary tee is a plumbing fixture that allows liquids to drain while also allowing the plumbing system to vent. The fitting resembles a normal tee fitting; the sanitary tee, however, when viewed from the side will have a definite downward sweep to the center inlet.

What's the purpose of a sanitary tee?

A Sanitary tee refers to a plumbing fitting used to drain water and vent the plumbing system. It connects the branch line to a vertical line. If you view the tee from the side, you will see a downward sweep, which is molded into the tee. It helps liquids to go toward the drain.