Although people who use walking aids can manoeuvre through door openings of 900 mm clear width, they
FIG. 15 PREFERRED COMFORTABLE TURNING RADIUS
need wider passageways for comfortable gaits as shown in Fig. 16. Crutch tips, often extend down out at a wide angle, and are hazardous in narrow passageways where they might not be seen by other pedestrians.
B-1.1.3 Space Allowance for White Cane Users Following shall be ensured for white cane users:
a) Protruding objects, such as directional signs, tree branches, wires, guy ropes, public telephone booths, benches and ornamental fixtures shall be installed with consideration of the range of the white cane of a person with vision impairment.
b) A barrier to warn blind or visually impaired person shall be provided under stairways or escalators so that they don't accidentally enter
in to them.
c) Walkways, halls, corridors, passage ways, aisles, or other circulations spaces shall have clear headroom to minimize the risk of accidents.
d) Adequate space allowance should be made considering that the radial range of white cane is a band of 900 mm wide (see Fig. 17).
e) Any obstacle above 300 mm cannot be detected by the white cane. If there are projections above this height then the same has to be treated in accordance with B-2.6.2.
B-1.2 Reach Range
A wheelchair user's movement pivots around its shoulders (see Fig. 18). The range of reach (forward and side; with or without obstruction) of a wheelchair users, as given in B-1.2.1 to B-1.2.3 shall be taken in to consideration.
B-1.2.1 Forward Reach
The maximum forward reach without obstruction is from the floor and the minimum forward reach without obstruction is from the floor as shown in Fig. 19.
The maximum forward reach over an obstruction is from the floor as shown in Fig. 20, which also indicates the touch reach and grasp reach.
B-1.2.2 Side Reach
The maximum side reach without obstruction is from the floor and the minimum side reach is as shown in Fig. 21.
The maximum side reach over an obstruction of size 860 mm high × 500 mm deep is 1 200 mm from the floor as shown in Fig. 22, which also indicates the touch reach and grasp reach.