Colour code standards for schematic diagrams

Hi Everyone.


I was asked the other day, if there are any laid down standards when it comes to colouring in schematic or block diagrams that are used in training. I have never come across anything myself in either the military or civilian sector but I wondered if anyone else had? I normally use red, blue/black and green for electrical cables but have never really considered any others.


If you have any useful info on this one then please post it here as I am sure it will be useful to everyone.


Many Thanks,




PS. I've also raised this discussion in content development to see if anyone in that group has ideas/

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  • There are web safe colors which are standard, though this has more to do with viewing accross a range of platforms.

    I do remember that there is guidance on using colours with regard to visually impaired people (i.e. colour blind people may confuse red and green etc)

    Also I have found information with document preparation to limit the number of colours to use.

    It also goes without saying the type of colours you use and there intensity can have an impact i.e. a hard green/yellow/red could be uncomfortable to look at, but softer pastel colours are more nicer on the eyes.

    Then there is the background colour scheme that would effect text and block colour.

    By working with a limited pallette and manipulating these colours with shading, shadows, highlights you should get some great results.

    There is also a wide range of info on colours in relation to mood out on the web.


    • Many Thanks for this Tim.

      From all my research so far it seems that there isn't any laid down standard for this type of thing, it is more to do with, as you say, meeting the needs of the specific learner (e.g. colour blindness, dyslexia etc).

      I shall continue the research and see what I find.
  • Richard,

    You may wish to refer to IEEE for colour specific international standards.
    • Many thanks for the info Dennis.
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