Curb ramps, also known as curb cuts, help people with disabilities safely and independently negotiate level changes on public sidewalks and other pedestrian routes.
Where pedestrians are expected to cross a roadway, or access a roadway to board a vehicle, a curb ramp or a depressed curb (see Section 2.1.6) provides a smooth transition for people who use mobility aids. Tactile walking surface indicators are required to warn people with visual disabilities that they are entering a potentially hazardous area.
Tactile walking surface indicators (TWSIs) at curb ramps consist of a band of material across the width of the curb ramp, of a different texture and with a high tonal contrast to the remainder of the curb ramp. TWSIs must be raised above the surface of the curb ramp, be detectable by a person using a long white cane, and be detectable underfoot. To be effective for people with low vision, tonal contrast between materials can be achieved by selecting materials that have a difference of at least 70% in their light reflectance values (LRV). Refer to Figure 220.127.116.11 for further details on measuring LRV
The choice between providing a curb ramp or a depressed curb (see Section 2.1.6) at a level change or pedestrian crossing depends on site characteristics, volume of pedestrian traffic and space availability.
This section includes requirements for curb ramps, which should be aligned with the direction of travel, sloped according to the difference in elevation of surrounding surfaces and include tactile walking surface indicators.
The requirements of this Section apply to newly constructed and redeveloped curb ramps in public spaces, except those located in a barrier-free path of travel under the jurisdiction of Ontario’s Building Code, such as along routes within a site to barrier-free entrances, passenger loading zones and parking lots with barrier-free parking.
Requirements for the Design of Curb Ramps
- Clear width
- Minimum 1,200 mm (exclusive of any flared sides).
- Running slope
- Elevation change less than 75 mm: No steeper than 1:8. (12.5%)
- Elevation change 75 mm -200 mm: No steeper than 1:10 (10%).
- Curb ramps along an exterior path of travel must align with the direction of travel.
- Cross slope
- Not steeper than 1:50. (2%)
- Flared side slope
- Not steeper than 1:10. (10%)
- Tactile walking surface indicators (TWSIs)
- Location: Provide TWSIs at the bottom end of curb ramps used for pedestrian crossings.
- At least 610 mm in depth
- Extend the full width of the curb ramp, set back 150 mm - 200 mm back from the curb edge.
- Profile: Tactile elements raised above the adjacent ground surface.
- Tonal Contrast: High tonal contrast to differentiate the TWSI from the adjacent ground surface.
NOTE: Clear width of walkway at the top of a curb ramp to be 1200 mm minimum to serve as a turning space, as per section 2.1.1 Sidewalks and Walkways.
Better Practice Considerations
- Running slope
- Consider a slope no steeper than 1:12 (8.3%)8.3%), to help users with strength or stamina limitations.
- Clear width of walkway at the top
- Consider providing at least 1,500 mm to better-accommodate the turning radius of scooters and larger wheelchairs.
- Orientation at pedestrian crossings
- Consider making the curb ramp align with the curb ramp or depressed curb on the opposite side of the roadway.
- Tactile walking surface indicators
- Refer to Appendix F - CSA Standards for Tactile Warning Surface Indicators. Truncated-dome type TWSIs are widely recognized as a ‘stop’ signal to pedestrians. Other TWSI configurations may not be as effective in providing the ‘stop’ message.
- Tonal contrast
- To enhance the definition of the TWSI, consider a difference of at least 70% between the light reflectance value (LRV) of the TWSI surface and the adjacent ground/floor surface.
Figure 18.104.22.168 Measurement using LUX Meter
(Having an acceptance angle of 60 degrees)
Step A) Place sensor of LUX meter in centre of surface of minimum 500 mm in diameter and measure the luminance (Ei).
Step B) Place sensor towards the surface and measure luminance (Er) at a height of 100 mm above and parallel to surface.
Step C) Repeat steps A and B two additional times, for a total of three measurements.
Step D) Calculate the effective reflectance coefficients (R) for each of the three measurements using the following formula:
Step E) Calculate the visual contrast using the following formula:
Where R1 is the mean effective reflectance coefficient of the lighter surface.
Where R2 is the mean effective reflectance coefficient of the darker surface.