The human vertebral column is the vertebral column (backbone or spine) of the human skeleton, consisting of 24 articulating vertebrae and 9 fused vertebrae in the sacrum and the coccyx.he human vertebral column is the vertebral column (backbone or spine) of the human skeleton, consisting of 24 articulating vertebrae and 9 fused vertebrae in the sacrum and the coccyx.
ADA Clear Doorway widths. Two doors in series must have a minimum of 48â in addition to the width of the door(s) swinging into the space (so a 36â door swinging into a hall would require the hall to be a minimum of 7â-0â long before any other door could be placed, if the second door does not also swing into the hall).
Width and Height Requirements: By ADA standards, the clear width of a door opening must be a minimum of 32 inches and a maximum of 48 inches. This clear width measurement is taken between the face of the door and the stop of the frame with the door open to 90 degrees (Figure A). Figure A.