Code excerpt regarding technical requirements for turning spaces: general, floor or ground surfaces, size, and door swing.
11B-304 Turning space
11B-304.1 General. Turning space shall comply with Section 11B-304.
11B-304.2 Floor or ground surfaces. Floor or ground surfaces of a turning space shall comply with Section 11B-302. Changes in level are not permitted.
Exception: Slopes not steeper than 1:48 shall be permitted.
Advisory 11B-304.2 Floor or ground surface Exception. As used in this section, the phrase “changes in level” refers to surfaces with slopes and to surfaces with abrupt rise exceeding that permitted in Section 11B-303.3. Such changes in level are prohibited in required clear floor and ground spaces, turning spaces, and in similar spaces where people using wheelchairs and other mobility devices must park their mobility aids such as in wheelchair spaces, or maneuver to use elements such as at doors, fixtures, and telephones. The exception permits slopes not steeper than 1:48.
11B-304.3 Size. Turning space shall comply with Section 11B-304.3.1 or 11B-304.3.2.
11B-304.3.1 Circular space. The turning space shall be a space of 60 inches (1524 mm) diameter minimum. The space shall be permitted to include knee and toe clearance complying with Section 11B-306.
11B-304.3.2 T-Shaped space. The turning space shall be a T-shaped space within a 60 inch (1524 mm) square minimum with arms and base 36 inches (914 mm) wide minimum. Each arm of the T shall be clear of obstructions 12 inches (305 mm) minimum in each direction and the base shall be clear of obstructions 24 inches (610 mm) minimum. The space shall be permitted to include knee and toe clearance complying with Section 11B-306 only at the end of either the base or one arm..
11B-304.4 Door swing. Doors shall be permitted to swing into turning spaces.