Australian Standard Requirements
Australian Standard AS 1428.1-2009 says that:
Luminance contrast between building elements is the difference in the amount of light reflected (luminance reflectance) from the 1st building element compared to the amount of light reflected from the 2nd building element.
The first building element has to have a minimum luminance contrast of 30% compared to the amount of light reflected from the second building element. It may be necessary to test both elements when wet and dry.
The test to be conducted may be carried out in the laboratory and on-site, and for published results to then be compared.
The luminous reflectance value (or ‘Y’ value) of the CIE 1964 colour system is recognized in AS/NZS 1580.601.2.
Minimum Requirements & Best-practice Ideas
There are minimum luminance contrast requirements, mandated in applicable building and disability legislation, but there are also best-practice ideas too, which can be adopted to improve the built environment.
These are discussed on this website.