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What colour blindness or Colour Vision Deficiency (CVD) is, how it affects day-to-day life, how to support pupils with CVD.

Colour blindness, also known as Colour Vision Deficiency (CVD) is a condition in which certain colours cannot be distinguished.

It's most commonly due to an inherited condition. 

Forms of CVD include:

  • red and green CVD: by far the most common form, about 99%, it causes problems in distinguishing reds and greens
  • blue and yellow CVD, which is rare
  • total CVD: seeing in only shades of grey, which is extremely rare

CVD seems to occur in about: 

  • 8% to 12% of males of European origin 
  • one-half of 1% of females of European origin

There's no treatment for CVD. 

CVD is not usually the cause of any significant disability. However, it can be frustrating for those affected by it.

Being colour blind can:

  • keep a person from performing certain jobs
  • make other jobs difficult 

Day-to-day issues that CVD may cause

People with CVD might have problems with:

  • colouring, for example when they have to use the blue crayon, not the pink one, to colour the ocean
  • weather forecasts, where certain colours cannot be distinguished
  • maps, because of the various subtle shades of colours generally used
  • traffic lights and caution lights: colour blind people have to know the position of the colours on the traffic light 
  • colour observation by others, for example pointing at the colours of flowers 
  • clothing, for example matching an outfit
  • observations during Science lessons
  • cooking and foods: people with CVD might not be able to tell: 
  • whether a piece of meat is raw or well done
  • the difference between green and ripe tomatoes
  • the difference between ketchup and chocolate syrup
  • some food, which can look unappetising to colour deficient individuals

How to support pupils with CVD

Ways to support pupils with CVD include:

  • colouring pencils with the name of the colours written on the side
  • on a map, features can be distinguished by photocopying the map in colour and marking the features in black or using a strong primary colour to show the area being focussed on
  • using black font on the whiteboard, as opposed to yellows, reds, and so on
  • using shading in graphs, charts, and whiteboards instead of requiring the student to see colour to disseminate the information
  • labelling items that require colour recognition
  • maximising colour contrast where possible, for example wall display background with the colour of the pages the children have done their work on

Contact us
Sensory Support Service
Elmfield House
Greystoke Avenue
Westbury-on-Trym
BS10 6AY

Phone: 0117 903 8442
Text: 07407 814 763
Email: sensorysupportservice@bristol.gov.uk