"William Gothberg" "William wrote in message
news
On Mon, 17 Dec 2018 01:17:39 -0000, % % wrote:

On 2018-12-16 6:10 p.m., Rod Speed wrote:


"Kristy Ogilvie" wrote in message
news On Sun, 16 Dec 2018 15:39:40 -0000, Steve Walker
wrote:

On 16/12/2018 15:00, Max Demian wrote:
On 16/12/2018 13:33, Kristy Ogilvie wrote:
On Sun, 16 Dec 2018 12:37:49 -0000, newshound
wrote:

On 14/12/2018 18:22, Fred Johnson wrote:
People with colour blindness shouldn't drive trains (or cars for
that
matter).

And it's not very many, in fact I know of only one person who's
colourblind.

You may not know *of* many but I bet you know quite a lot. It's
about 8%
of men, although many of them do not realise that, or discover it
until
tested later in life.

I think you'd notice when you saw all the traffic light bulbs
looking
identical. You're not safe to drive if you can't tell red from
green.

I suspect they don't look *identical*, just not as distinct as to
someone with normal colour vision. They would use the position to
confirm which is which.

Correct. Which is why colour-blindness is not even notifiable to the
DVLA. Driving a train is of course totally different as braking needs
to
be commenced way earlier and the position of the light cannot be
determined at that point.

I'm not colour blind, and I don't look directly at the traffic
lights. I see red or green out of the corner of my eye and act
accordingly. If they suddenly became the same or very similar colours,

That isnt what happens with most colorblind people.

And its never suddenly with any of them, they are born with it.

I'd make mistakes regularly.

Yes, some colorblind people do, but its normally only
with trivial stuff like not being able to pick matching
sox or less frequently wearing contrasting colors that
don't really go together that only normally sighted
people notice.

Are you saying a colour blind person already knows to look carefully
at things?

The microscopic subset of people that can't distinguish
between red and green do if fact use which of the
column of lights is lit instead of the color.

I can't think of where else colour and position are that important.

The most obvious is with signalling to aircraft
in the days before radio communication was
used. They used red or green light to indicate
whether you were allowed to land or not
depending on what else was using the runway.

the radio was invented first so that's just stupid ,
and what did they do in the day time , yell out the plane window ,
what a freakin jerk nosed pig footed ear grabbing habit face

Was that supposed to be English?

Nope, canuck.