...you’d not be subjected to mainline conditions such as changing signals/travelling through numerous different areas at speed and adjusting to these conditions day and night with limited artificial lighting.
Most of which doesn't matter, you either see the colour or not. Conditions like weather will affect everyone but the shade of colour will still be the same.
It shows how little information people know about colour blindness. It's not anyone's fault but people get uppity if they're told that's now how it is.
Most people seem to think you can't see red or green. Really? What do you think they see? A world full of grey?
I don’t think it’s discrimination, I think it’s about safety and mitigating possible risk. The railway has relaxed some vision rules over the years to bring themselves in to the 21st century (such as allowing higher prescriptions and laser eye surgery etc.).
This is it.
There are 100 other candidates so no need to take the risk with someone who has a colour deficiency.
But what's difficult for some people to understand is that for some people with certain levels of colour blindness, there would be ZERO risk.
Being colour blind isn't black and white. There are many levels, some people really struggle while others can see fine, just not pass a 103 year old test.
I can't think of a single thing we use now that's over 100 years old. Wine maybe...