LightLab International

Luminous Reflectance

Luminous reflectance of tactile indicators and other surfaces.


AS1428.4 sets out requirements for new building work, for the design and application of tactile indicators, to ensure safe and dignified mobility of people who are blind or vision impaired. To do this the luminious contrast between the Tactile ground surface indicator (TGSI) and adjacent surfaces must be determined. LightLab offers a testing service that satisfies this need by accurately quantifying the surfaces in terms of luminious reflectance or contrast.


Results can be issued using either of the two test methods set out in F3 and F5 of the standard. Using these results the Luminious contrast can be determined to proove suitability of materials.

Depending on your application you can choose between:-

F3)   Determining a Luminous reflectance (Yd or Yw) for a material. This result is specific to the product tested, and provides a value that can be used to determine the contrast between it and other known surfaces. This is useful to manufacturers in providing specifications of their product to their customers. Results can be determined for both wet and dry applications.

F5)   Measurement of luminance contrast. This is a site specific method, typically the test is carried out under the prevailing lighting and weather conditions.

Each category and sample type has a defined test report format containing a summary of the test measurements and a pass/fail summary if required by the standard.