Understanding Accessibility

Guideline 2. Don't rely on colour alone.

Colour blindness and some types of dyslexia mean that people with these disorders may not be able to see various colour combinations properly. For example, if a text hyperlink is green in the normal state and red in the rollover state, people with red-green colour blindness may not realise that the text is a link, as there would be no perceived change on colour on rollover. This guideline specifies that no elements should rely solely on colour to be recognised.

There are 2 specific checkpoints in Guideline 2.

Guideline 2 checkpoints, ordered from 1 to 2, with priority and how to check the checkpoint given and the disabilities accommodated by applying the checkpoint
No. Checkpoint Priority Disability Accommodated
2.1 Ensure that all information conveyed with colour is also available without colour, for example from context or markup. Priority 1 Colour Blind
2.2 Ensure that foreground and background colour combinations provide sufficient contrast when viewed by someone having colour deficits or when viewed on a black and white screen.

Priority 2 for images

Priority 3 for text

Partially Sighted

Colour Blind

guideline 1 - 2 - 3 - 4 - 5 - 6 - 7 - 8 - 9 - 10 - 11 - 12 - 13 - 14