Priming of Steel Beams (1) Exterior steel beams susceptible to corrosion shall be shop primed with rust-inhibitive paint. Article 9.23.8.2. Ontario Regulation 332/12 Building Code, Information published by oncodes.ca for educational purposes only. Similar articles Continuity of the Air Barrier System Bearing of Beams and Joists Support of Tail and Header Joists Floor Framing