It should be erected by the scaffolder according to the special safety construction organization design (construction plan) or safety technical measures. Ventilation duct installation The load-bearing operation platform used for installation shall be erected by the scaffolder according to the special safety construction organization design (construction plan) or safety technical measures. It can be used only after passing the acceptance check. The protective railing on the feeding side of the operating platform should be restored in time. Materials or equipment parts shall not be stacked on the platform, and overloaded use is strictly prohibited. Ventilation ducts When installing steel frame beams in ducts, operators must wear safety belts when working at heights. Hands must not rest on the top of the beam. Before the beam and the column are welded firmly, it is strictly forbidden to operate by people. Duct processing