Welded connections on precast tilt ups.

Leko is not certified to CSA Standard W47.1 “Certification of companies for fusion welding of steel” and, therefore, does not meet the requirements of CSA S16 Clause 24.3 which is referenced in the National & Provincial Building Codes Section 4.3.4.1.
NBCC Section 4.3.4.1: "Building and their structural members made of structural steel shall conform to CSA S16 “Design of Steel Structures.”

CSA S16 Clause 24.3: “Fabricators and erectors responsible for welding structures fabricated or erected under this Standard shall be certified by the Canadian Welding Bureau to the requirements of CSA W47.1 (Division 1 or Division 2), CSA W55.3, or both, as applicable. Part of the work may be sublet to a Division 3 fabricator or erector; however, the Division 1 or Division 2 fabricator or erector shall retain responsibility for the sublet work.”