Design of built environments to accommodate mobility scooter users: part II.

PURPOSE.Accessibility standards for wheeled mobility devices currently use a 1.5 m turning circle, designed to accommodate manual wheelchairs. Scooters are less manoeuvrable than wheelchairs, so allowing a full turning circle would require too much space. Instead, we propose using a rectangle that provides space for a three-point turn. Here, we determine the area requirements of this approach. METHOD. For rectangular 'rooms' of varying aspect ratios, we measured the minimum dimensions in which two four-wheeled scooters (the Celebrity-X and Fortress-1700), which combine good outdoor performance with reasonable indoor manoeuvrability, could enter the space, perform a three-point turn and exit. Moveable Styrofoam walls defined each 'room', and a doorway was located either near the corner of the space or in the middle of one wall. 'Room' size was decreased until our expert driver could no longer perform the manoeuvre. RESULTS. Compared to the area required for a turning circle, 42-54% savings were achieved. Relative to existing requirements, 53-95% more space is required to accommodate the Celebrity-X; 173-223% increases are necessary for the Fortress-1700. CONCLUSIONS. When accommodating four-wheeled scooters, our proposed three-point turn definition would require more space than the current standards, but considerably less than if a full turning circle were used.