S.C. Code Ann. § 5-25-850

Where a stairway, elevator or dumbwaiter shaft extends through the roof and is covered with a skylight, the skylight shall be constructed with incombustible frame and sash, glazed with ordinary thin glass, and shall be protected by a galvanized steel wire screen with a mesh not exceeding one inch and the wire not smaller than No. 12 gauge. The screen shall have metal supports and shall be placed not less than six inches above the skylight. Instead of a skylight, a window may be placed in the side of the shaft above the roof which is furthest removed from a property line. The window shall have incombustible frame and sash and be glazed with thin glass.