République Française (liberté, égalité, fraternité) Inria

Colour blindness

Colour blindness is a form of visual impairment that affects how people see colours.

There are multiple types of colour blindness, which can be broken down into 7 families.

  • 4 families of « red-green » colour blindness
  • 2 families of « blue-yellow » colour blindness

Roughly 8% of men and 0.5% of women struggle with colour perception.

Information & colour

What do you think of these graphics ?

Colour perception differs from one person to the next.

Information conveyed exclusively by colour may not be perceived by some people who are color blind or visually impaired, for example.

Example of chart not accessible

Circle chart of 6 information on the Administrative Recognition of Disability, given only by color (detailed description below).

Detailed image description

Administrative recognition of disability

Source : Insee 2015

  • disabling disease 21%
  • Physical disability 46 %
  • Visual impairment 5%
  • Mental and cognitive disability 7%
  • Hearing impairment 8%
  • Psychic disability 13%

The keyrs are represented using colour alone

Making it difficult for people with colour blindness to pick out information.

Example of an accessible chart

Circle chart of 6 information on the Administrative Recognition of Disability, where color is not the only vector of information: the data is grouped and understandable regardless of color perception (detailed description below).

Detailed image description

Administrative recognition of disability

Source : Insee 2015

  • disabling disease 21%
  • Physical disability 46 %
  • Visual impairment 5%
  • Mental and cognitive disability 7%
  • Hearing impairment 8%
  • Psychic disability 13%

The keys can be understood regardless of the colours used.

Alternative formatting means information is conveyed irrespective of the colour.

Things such as textures, shapes and clear headings can also be added to allow people with colour blindness to access information.