Colourblindness and engineering drawings

[edwin_m]

A slight presentational grizzle:
About 1 in 12 of the UK male* population is colourblind, with red-green colourblindness being the most common. Presenting people with diagrams where red lines and green lines are intermixed but mean opposite things is just plain ignorant, and could be described as discriminatory. Yes, I am aware of the usual railway standards on signalling diagrams, but this is a document designed to be read and used by the general population. It is utterly useless for me - and millions of other people like me.

* It is a genetic condition which is very rare in females.

My middle brother is red-green colour blind. So may I ask, in your opinion, what colours would you make the lines on the electrification maps?

I'd cope with red, yellow, blue - others might have some issues with that combination, I don't know for sure.
Better still some combination of changed colours and dotted / dashed / solid lines.

I do alright with that map but the electrification map in last months Modern Railway's was a nightmare for me, too many blues which all look the same to me. (I am a bit odd in that Green & Red are fine but red / brown and shades of blue are not).

I am NOT colour blind and am in fact a trained colour matcher for paint batches etc. However, although I very much lauded the David Shirres article, even when printed out the two shades of blue were extremely difficult to make out. I actually think black would be a good choice for some lines.

I'm not colour blind but I did once have a CEO of client who was Red-Green colour blind so were were pretty good on making sure everything was done right.
I ran the 2035 Red-Yellow-Green map through a colour blindness image tester and unsurprisingly Red-Green is an issue but the is a line thickness difference between red and green which does help a tiny bit (scraping barrel for something positive)

What they could have done better:
Accentuate differences by using greater difference in thickness of line.
Use different line texture / patterns
Make sure there are tonal differences e.g. a washed out red and deep green, e.g. if you print it out in Black and White could you tell the difference?
Use colour blind friendly palettes, a good start is using the IEC electrical wiring colours e.g. Brown-Blue-Grey-Black-Orange-Green-Purple (1st 4 also happens to have good tonal difference) or Tube map colours minus central line as they have been carefully tweaked.

The only signalling diagrams that use colours other than black and white are those involved with the commissioning of new works. If that were a new works diagram, green would mean that the lines/equipment were being removed, and red would mean new lines/equipment being built (With blue for those awaiting a decision). No yellow in any diagram as it can easily be overlooked, especially in low light. We don’t otherwise use colours on standard signalling diagrams, instead signals are represented using specific symbols and can be read by a trained member of staff regardless of any colour blindness (Though, that may prevent you passing a medical depending on its severity).

This colour coding tends to be used more widely for development of new works not just commissioning and not just signaling either, though I believe track engineers use blue for track that moves a bit but not enough for separate red and green to be distinguishable. I don't do plans myself but in PowerPoint etc I try to make the green ones thinner or dashed. This was never a problem in British Rail as nobody would be accepted for any role unless they had good colour vision, but there's no real reason for that to apply to non-operational roles and I've worked with at least one engineer with red-green colourblindness.

I wonder if that's why the widely-understood terms "red zone" and "green zone" were dropped as well.

 

[GRALISTAIR]

Glad this thread has started - it did clutter up the other one slightly.

 

[CW2]

<SNIP> This was never a problem in British Rail as nobody would be accepted for any role unless they had good colour vision.

Not so sir! I myself entered the industry as an employee of British Rail. I started on the commercial side then transferred across via Control into Operations Planning and Project Management.

 

[edwin_m]

Not so sir! I myself entered the industry as an employee of British Rail. I started on the commercial side then transferred across via Control into Operations Planning and Project Management.

Interesting. I joined Research in 1987 and the appointment was subject to a colourblindness test despite no intention to be in an operational role.