Please see attached SANS 10400 Part S Facilities for persons with disabilities

As per these standards the design of ramps should not be less than below:

4.8.1 Any ramp or series of ramps shall provide a safe, comfortable and convenient route for wheelchair users.

4.8.2 Any ramp provided in terms of this part of SANS 10400 shall

1. have a gradient, measured along the centre line, that is not steeper than 1:12 ;
2. have a clear, trafficable surface not less than 1 100 m wide;
3. have a surface in accordance with 4.5;
4. have a landing at the top and bottom of each ramp of not less than 1,2 m in length (clear of any door swing) and of width not less than that of the ramp;
5. comply with the requirements between landings as given in table 2 and figure 11;
6. have a handrail on both sides of the ramp or, where the width is greater than 2,4 m, a central handrail in accordance with the requirements of 4.10 where the gradient is steeper than 1:15;
7. where ramps in the same direction are used for a vertical rise of more than 600 mm, be staggered by the width of the ramp, in order to prevent a long straight line of ramps (see also 4.8.2(d)).

4.8.3 No door leaf or window shall open onto a ramp or landing (see also 4.8.2(d)).

4.8.4 The camber or banking on walkways and ramps shall not exceed 1:50, as shown in figure 4.

4.8.5 At any point where the clear height of the area below the soffit is less than 2,1 m, and it is not enclosed, the means of limiting inadvertent access to such area shall be indicated.