Colour is often used in charts, maps and infographics, but what if you can’t see some colours? One in twelve men are colour blind, but not for all colours or the same colours. Infographics are becoming more popular as a means of explaining things. So choosing the best colours is to everyone’s advantage. Venngage website has an good guide and lots of tips on making charts more accessible. It shows the three types of colour blindness and compares them with normal vision. Different colour palettes are provided along with templates. The blog page includes links to other resources. Colour combinations to avoid include:
- Red & green
- Green & brown
- Green & blue
- Blue & gray
- Blue & purple
- Green & gray
- Green & black
Most colour blind people can detect contrast, so as a last resort, if you must use these colours, make the contrast as strong as possible. Patterns and textures also work. The article is titled, How to use color blind friendly palettes to make your charts accessible. Colour blindness is technically referred known as colour vision deficiency (CVD).
Another resource for map colour by Tedora Zareva is useful too. You can also find out more about CVD or colour blindness from going to the National Eye Institute website
Which colour to use – A new standard?
There is a growing body of science on the topic of colour use and choice. On the second page of the International Ergonomics Association newsletter there is an item advising that in developing an international standard (ISO 24505) for colour use, accessibility needs to be considered. In four parts, the first part of the standard has been published for older people taking into account age-related changes in human colour vision. The remaining three are under development. Here is a snippet from the newsletter: