Luminance Contrast Calculator

Luminance Contrast is the amount of light reflected from one surface or component, compared to the amount of light reflected from another surface or component. The amount of light reflected from each surface or component is referred to as the Luminance Reflectance Value (LRV).

Many manufacturers and suppliers provide the luminance reflectance values for their products, however there are a number of materials that have variations within each material and between batches, such as timber, stone and concrete, which cannot be assigned an LRV without testing the finished installation.

Realm Access provides luminance contrast testing services. During the design phase we can test samples to provide peace of mind the proposed finishes will achieve a compliant contrast. We also provide on-site testing of constructed works for final compliance sign-off.

If you would like further information or a quote for luminance contrast testing for your project, please do not hesitate to contact us. 

Minimum Luminance Contrast Requirements for Compliance

For buildings and premises that are subject to the National Construction Code / Building Code of Australia (NCC / BCA), the Disability (Access to Premises – Buildings) Standards (often referred to as the Premises Standards), and the Disability Standards for Accessible Public Transport (DSAPT), there are mandatory requirements to provide minimum levels of luminance contrast to certain elements within accessible areas as outlined in the lists below. Please note the lists do not include other potential requirements such as local government and approval authority requirements, NDIS Specialist Disability Accommodation (SDA) Design Guideline requirements, Changing Places Design Specification requirements, or best-practice to meet the intent of the Disability Discrimination Act 1992 (DDA).

Minimum 30%

  • Integrated Tactile Ground Surface Indicators (TGSIs) or ‘tile’ type TGSIs which have indicators with the same luminance as the base surface

  • Doorways

  • Stair nosing strips

  • Visual indicator strips / glazing decals

  • Toilet seats in accessible sanitary facilities and accessible adult change facilities

  • Statutory signage for sanitary facilities, areas with hearing augmentation, exits and some directional and wayfinding signage

  • Lift control buttons

  • Handrails (for public transport projects)

  • Potential obstacles that abut accessways such as columns, posts, poles, seating and other furniture (for public transport projects)

Minimum 45%

  • Discrete Tactile Ground Surface Indicators (TGSIs) which are the individually installed TGSIs which have a top surface that has the same luminance as the sloping sides

Minimum 60%

  • Composite Discrete Tactile Ground Surface Indicators (TGSIs) which are the individually installed TGSIs which have a top surface that has a different luminance to the sloping sides

This calculator uses the Bowman-Sapolinski equation as outlined in Appendix B of AS 1428.1 (in both the 2009 and 2021 revisions) and Appendix E of AS/NZS 1428.4.1 (2009):

C = 125(Y2 - Y1)/(Y1 + Y2 + 25)

C = the Luminance Contrast of two surfaces

Y1 & Y2 = the LRVs of each surface obtained with a tristimulus colorimeter or spectrophotometer

Please note this calculator is intended as a guide only. Realm Access accepts no liability for its use or misuse, or the accuracy of results.