Disability access legislation and Australian Building Code require public buildings to comply with AS 1428.1 Design for access and mobility – General requirements for access –
New building work. AS 1428.1 identifies that visually impaired people require warning signs for hazards when wayfinding through public premises.
These signs are tactile whereby visually impaired people can feel through their feet or visual aids and are known as Tactile Ground Surface Indicators or TGSI’s for short.
There are requirements which determine the size shape and colour as outlined within AS/NZS 1428.4:2009 Design for access and mobility – Part 4.1: Means to assist the orientation of people with vision impairment Tactile ground surface indicator.
One important aspect of TGSI’s is to provide luminance contrast.
TGSI’s serve to inform visually impaired people of either information to direct people to a point of interest (directional TGSI’s), or to warn people of a hazard (warning TGSI). Directional TGSI’s are long bars indicating a direction of travel and warning TGSI’s are small dots or bumps. The correction dimensions and location in relation to the hazard is critical to ensure safe wayfinding for visually impaired people and consistent information and feedback to make the correct informed decisions required to be made.
Where should TGSI be used?
• Where ever the public has access to a building or area.
• A platform where any rail, tram, bus or ferry stops.
• At the bottom and top of step(s), stairs, escalators, travelators, ramps, curb ramps, cross paths, etc.
• Around any overhead impediment or hazard other than a doorway with less than a 2 metre clearance in an accessible open public space eg. Fire hose reels, drinking fountains.
• Water bodies or other item or feature of significant risk eg. Paved or built river embankments, rail/tram level crossings.
• Placement of all TGSI must be in compliance with AS1428.4:2002 and should not be proliferated unnecessarily.
Frequently Asked Questions
(for more information refer to AS1428.4)
What are Tactile Ground Surface Indicators (TGSI)?
TGSI’s provide cues, which, when combined with other environmental information, assist people who are blind or vision impaired with knowing what direction they need to go and if they are going to encounter a hazard.
Why has the placement of TGSI become mandatory?
Over the coming years many ageing Australians will find themselves with some form of vision impairment. The Building Code of Australia (BCA), Australian and New Zealand Standards (AS/NZS), The Disability Discrimination Act (DDA) and other regulatory bodies have established a mandatory Code of Practice for the inclusion of TGSI to the vision impaired in avoiding accidents in hazardous or high traffic areas. In accordance with that Code of Practice, the Australian and New Zealand Standard 1428.4:2002 states that TGSI are required to be installed in all new environments that could be deemed dangerous to the vision impaired, disabled and elderly.
Why Vision impaired people?
A vision impaired person is one who needs glasses, which is a large and ever growing section of the community. This is why TGSI colour contrast is important as many people with vision impairment will use the colour contrast to visually detect the indicator. TGSI should have a 45% luminance difference to the background or base surface.