A. Usually, rotating stairs are not used as the main evacuation function.
B. Step width of inner handrail ≥220mm.
C. Ladder height ≥2200mm, railing height ≥900mm, platform ≥1050mm.
D. The slope of the stairs should not be too steep (usually less than 38°), and the height and width of the steps should meet the requirements of the corresponding building type.
E. When making decorative surface layer on the stepping board, cement mortar should be used for leveling the stone, but it is easy to appear "empty drum" or "cracking", so it is suggested to consider using wood as the base.
F, steel structure construction and installation mode is mainly welding, although all components have been prefabricated rust treatment, but in the welding process may be destroyed, so the welding position needs to pay attention to, if the damage to brush anti-rust paint.
