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Tactile Ground Surface Indicators (TGSI)

Warning TGSI positioned before a staircaseTactile ground surface indicators (TGSI) are raised domes and stripes placed in patterns on the ground to provide tactile information. Their colour and luminance contrast provides information to people with vision impairment about hazards and directions.

Two types of TGSI are currently used in Australia, under Australian Standard 1428.4.

  • Warning Tiles: These indicate hazards such as platform edges, stairs and overhead obstacles. They also inform people about changes in the direction of path of travel.
  • Directional Tiles: These assist people to negotiate difficult environments such as wide open spaces or busy, dynamic spaces or to locate specific objectives such as the entrance and exit of train stations.

Directional TGSI positioned leading into a road crossingTGSI may provide useful clues to people with vision impairment. The consistent use and placement of TGSI is a key consideration during installation, however TGSI should not be overused.

Tactile ground surface indicators can be installed as:

  • Integrated units: Tile-like units, where the background and raised domes are made of the same material.
  • Discrete units: Separate domes installed to provide the effect of a tile on an existing surface. The raised domes are inserted into the background surface.

There are specific requirements for TGSI including:

  • Contrast
  • Hardness
  • Dome height and spacing

For more information, refer to Australian Standard 1428.4.


Vision Impairment

Vision Impairment

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