Every finish reflects some light, which is measured on a scale from 0 to 100 (called light reflectance value, LRV). The difference between the LRV of two finishes is the contrast.
One grab rail and the wall or floor should have at least 30 points of contrast in accessible sanitary areas inside buildings other than dwellings according to the English regulations (Approved Document M). People with visual impairments and conditions like dementia require that these fittings have this minimum contrast with the surrounding surfaces in case of average light situations.
For instance, in case of a white painted wall (value around 85), a grab rail with a darker finish should be chosen (55 at most), like brushed stainless steel or blue.
The examples below are illustrative.
|Illustrative light reflectance values (LRVs)|
|Orange, light blue, light green||40-60|
|Polished stainless steel||40-60|
|Brushed stainless steel||40-45|
|Proper green, blue or red, dark grey||10-25|
Check the LRVs of the products involved by consulting the technical sheet your manufacturer may have provided you. If they have not, you could do some research on the exact shade of colour (there are dozens of blue, each one with a different value: cobalt, indigo, sky, teal...). Also consider the finish; metal, glass, wood or plastic do not cause the same reflectance.