The Ontario Building Code | Size and Thickness

9.17.3.1. Size and Thickness

(1) Except as permitted by Sentence (2), steel pipe columns shall have an outside diameter of not less than 73 mm and a wall thickness of not less than 4.76 mm.

(2) columns of sizes other than as specified in Sentence (1) are permitted to be used where the loadbearing capacities are shown to be adequate.