[safety4all]

Can you Distinguish between Red Signal and Green Signal?

About 13 million people in India are Color Blind and they often can't see the difference between a red and a green light.

Are you Color Blind?
Here is a short test to find out!
Click here http://vzturl.com/gc12

Color Blindness, medically known as Daltonism or deuteranopia is a common malady, especially among men. Color vision deficiency is defined as the inability to perceive differences between some or all colors that other people can easily distinguish. Most often it’s genetic, but it can be caused by other reasons.

[shankar.balan]

Sad isnt it?

Thankfully I have a high sense of colour and shades and nuances of colour.

[srishiva]

Hope not many of these 13 million are drivers ! Should they be tested while issuing license? (would be sad if such people cant drive)

[Fillmore]

Actually you can make out by the position of the lights too
On a Vertical alignment Red is always at the top and Green is at the bottom.
On a Horizontal Alignment Red is the leftmost and Green's are at the right most.

[kamboj]

IIRC color blindness is checked during medical test for DL.

Anyways there is solution to this, red/yellow/green light are always in same order (top-down or left-right) so that should help color blind people decide if it is time to stop of go.

[drmohitg]

You are indeed checked for colour blindness when applying for a DL. This is ofcourse not applicable to all those people who go via an agent and bypass all these steps.

In general this problem is very common as mentioned by the OP. You will be surprised to see that sometimes these people don't know it themselves or fail to declare it while applying for a job etc. Just 6 months back in AIIMS Post Graduation exam, 2 of the top ranker students were not allowed to take admission since they failed the medical test and were colour blind.

[sushantr5]

Unfortunately, I am color blind person. I can't distinguish between red and green from far. For signals I do not have any problem. But if I see the same signal from 300-500 meters I can not tell which is what. Same goes with Violet and Blue, everything is perceived as blue.

I came to know about my color blindness in my school in 5th Std. I did not clear medical test for military schools.

In the color blindness test mentioned in first post (http://vzturl.com/gc12) I scored ZEROOOO.

I do not feel any difference with normal person in my day to day life. The difficulty arises only when I need to name the color. Red and Green I can recognize after looking at it constantly. Signals are instantly recognizable from normal distance. From far it is the problem. But in case of violet and blue, distance does not matter it is always blue.

[Gandhi]

Originally Posted by Fillmore

Actually you can make out by the position of the lights too
On a Vertical alignment Red is always at the top and Green is at the bottom.
On a Horizontal Alignment Red is the leftmost and Green's are at the right most.

You know that because you can distinguish between red and green. If someone is color blind, (s)he can't even figure that out until someone enlighten him/her .

[rohanjf]

The position of lights will work in developed countries, with their 'yield on left/right' rules. Here we have arrows that turn green or red at some junctions where not all turns are allowed at all times. How will a colour blind person deal with that?

[svsantosh]

Originally Posted by sushantr5

I came to know about my color blindness in my school in 5th Std. I did not clear medical test for military schools.

I do not feel any difference with normal person in my day to day life.

:( kudos to your spirit of driving.

[noopster]

I got the first 9 right. The last one I judged as 71 but it was 74 (looked that way because my monitor was at an angle- readjusted it later and saw some additional green dots I had missed). very revealing test.

Is there anything like relative colour blindness> i can imagine some people sail through a test like this while I had to pause and examine it closely in some cases. I have been having arguments with the women in my family as far back as I can remember on whether a particular colour is green or blue, red or maroon etc.

[safety4all]

I am sure that an opinion from an optometrist (eye specialist) would be best.
In any case this test is not a diagnosis test.

[mayankjha1806]

I failed the color blindness test given in the link above, but i can clearly make out red and green color signals (Never had a problem with those). I have been tested for all these eye aliments and have been cleared with good eye sight, hence the test given above is confusing and in no way indicative of color blindness. Putting numbers inside circles with color dots can get folks confused (As i was with two numbers).

So, i would say ignore the test like these and get eyes tested with a ophthalmologist, which should serve one well.

[rajni]

In my opinion, this test is for complex situations of color blindness. Those who fail in this might still be able to make out a red-yellow-green difference. I failed in the test, but I never had a problem in color sensing in the traffic. Yea, I agree that because I spend long time in front of computers my eye sight or color sensing abilities would have reduced. So, no worries, you can still live without a certificate from that site :-D. But, good to consult an eye doc.

[John]

Color blindness is an inaccurate term to describe a lack of perceptual sensitivity to certain colors, a more precise term is Color Vision Deficiency (CVD). Color blindness is, however, the most commonly used term though it is misleading if taken literally, because colorblind people CAN see colors, but cannot make out the difference between some couples of complementary colors. Color vision deficiency is not related to visual acuity at all and is most commonly due to an inherited condition. Red/Green color vision deficiency is by far the most common form, about 99%, and causes problems in distinguishing reds and greens. Another color vision deficiency Blue/Yellow also exists, but is rare and there is no commonly available test for it.

Read the rest of the article at:

http://www.archimedes-lab.org/colorblindnesstest.html