Color vision for network techs

William Astle lost at
Fri Aug 31 14:39:35 UTC 2012

On 12-08-31 08:15 AM, Berry Mobley wrote:
> Hello,
> Do any of you do any color vision screening in your interview process?
> How do those of you with color vision impairments compensate? I'd never
> considered this until I was in one of our facilities with my son (who
> has limited color vision) and we had a discussion about the LEDs. He
> could only determine on/off - not amber/red/green on the equipment we
> had. I'm wondering if we need a color vision requirement (or test) as
> part of our hiring requirements.

I'm red/green deficient. It's not total - I can identify high saturation 
reds and greens that cover a large enough area. However, it is enough 
that when I look at a multi-colour status indicator, I'm left scratching 
my head. Many times, I've said to myself, "There ought to be a law 
against using only the colour of light to indicate status." Of course, 
you know what they say about "there ought to be a law...."

Screening for colour vision is dubious, no matter how much it would help 
with grokking the status lights. Even without the discrimination angle, 
consider that a very nontrivial proportion of men are colour deficient 
(on the order of 5% if my information is correct). You would be reducing 
your possible talent pool.

Instead of a colour vision requirement or policy, I would start 
screaming at equipment manufacturers for using only the colour of an 
indicator to show information. A tristate can easily be shown with 
steady, slow blink, and fast blink if there really is some compelling 
reason not to have multiple indicators. If everyone, especially large 
organizations, put pressure on equipment manufacturers, the problem 
could be largely eliminated.

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