The Ontario Building Code | Sanitary T Fittings
7.2.4.2. sanitary T Fittings
(1) A double sanitary T fitting shall not be used to connect the fixture drains of two urinals where no cleanout fitting is provided above the connection.
(2) No pipe fitting, joint or connection that would tend to intercept solids or reduce the flow through a pipe by more than 10 per cent shall be used in a plumbing system.
In Plain Language
A double sanitary T fitting can't connect the fixture drains of two urinals unless a cleanout fitting is provided above the connection, and certain other pipe fitting and joint combinations are similarly restricted.
This is a plain-language summary of the 2012/2017 Ontario Building Code text above, for general understanding only and not a substitute for the Code. Always confirm current requirements against the 2024 edition (O.Reg. 163/24) or a qualified professional before construction.