ASD - Universal Accessibility for External Areas, Open Spaces and Green Spaces

3.	Best Practices and Guidelines

3.1	Access Route
3.1.1	Introduction
3.1.2	Design Considerations

3.1.3	Surface Treatment
3.1.3.1	Surface Treatment and Material
3.1.3.2	Difference in Flooring Materials
3.1.3.3	Pavement markings

3.1.4	Surface Drainage
3.1.5	Sensory and Psychological Needs
3.1.6	Elements along a Travel Path

3.2	Connectivity and Interfacing Elements

3.3	Landscaped Spaces

3.4	Furniture, Equipment and Fittings

3.5	Way Finding, Orientation and Signage

3.6	Detectable Surfaces

3.7	Colour and Luminous Contrast

3.8	Lighting

3.9	Safety

3.10	Management and Maintenance

3.1.3	Surface Treatment

3.1.3.1	Surface Treatment and Material

(a)	The floor surface must be firm and slip-resistant in both dry and wet weather conditions. It must be properly sloped for effective rainwater drainage.
(b)	The surface should be generally levelled. For cross slope gradients, refer to Section 6.2.2 of “Universal Accessibility — Best Practices and Guidelines”.
(c)	Any services on the ground, such as manholes, covered channels, and the like, should be flush with the floor surface (3.1.3.1a, 3.1.3.1b and 3.1.3.1c).
(d)	Expansion joints and gaps on the surface should be less than 13mm wide to avoid trapping wheelchairs and canes.
(e)	For a comparison of various external floor materials, refer to Section 3.9 — Safety.


3.1.3.1a Channel cover levelled with floor surface and gaps at the gratings are less than 13mm wide		3.1.3.1b Narrower channel grating slots provided at pedestrian crossing		3.1.3.1c Manhole covers levelled with the floor surface


3.1.3.2	Difference in Flooring Materials

(a)

The use of different floor surface materials can help in detecting and identifying the different access paths and zones within a large external space. For example, various floor materials with different colours and textures can be used to delineate walkways, resting areas, and recreational areas (3.1.3.2a). However, for the purpose of detection and identification, there should not be an excess of different surface materials. The different surface treatments should be designed consistently; otherwise it would not serve the intended purpose.

(b)

Where necessary, clear information should be provided at locations where there is a change in materials to alert users of such change.


3.1.3.2a Use of different floor surface materials to identify different zones in open areas


3.1.3.3	Pavement Markings

(a)	Markings on a pavement, such as warning strips at change in levels, should have colour contrast with the pavement (3.1.3.3a). Attention should be made to the suitability and durability of the pavement marking material for the particular pavement surface. The markings should be properly maintained and should be repaired or replaced immediately when damaged (3.1.3.3b).
(b)	Markings on pavements should not be excessive.
(c)	Pavement markings must not form a tripping hazard to users.
(d)	For detectable surfaces or tactile guide paths on pavement, refer to Section 3.6 — Detectable Surfaces.


3.1.3.3a Painted warning with colour contrast to adjacent floor finishes at road kerb		3.1.3.3b Markings should be properly maintained, worn-out makings should be repaired or replaced immediately