Both are standard atlases about roof ventilators, ventilation skylights, air towers, etc. regarding natural roof ventilation and lighting:
————"Ventilation Skylights" 05J621-3 is The large skylight in the national standard atlas is based on the patented polygonal combined ventilation skylight and arched combined roof ventilator, and later adds the thin skylight technology of double-side air duct ventilation units.
——"Ventilation and Lighting Skylights" 11cj33 is a national standard reference atlas. The main technologies are not much different from the structural form of 05J621-3, except that there are some different ways of fixing the weatherboard. The main ones in the standard are The patented technology "parallel duct type thin skylight technology" has been added, which is the so-called thin skylight technology of single-side duct ventilation unit.