Tag Archives: color

Color Vision Deficiency and Pool Maintenance

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When I was growing up, I can recall getting extremely excited every single year during the later portion of June. The reason for that excitement laid in the fact that at that point, in Long Island, the temperatures were finally hot enough for my family to open our pool in the backyard. That moment when my father would rip the thick, black winter cover off the top of the water’s surface was always a highlight of the summer. However, when that event finally occurred each year it was always such a tease; the water in the pool would be filthy with leaves, dirt, and dead insects that compiled throughout the off-season. Sure enough my brother, sister, and I would have to wait a few days longer for my father to clean the water with chlorine and other chemicals before it was safe enough for us to start swimming. However, the same problem arose every single year- my father could not align the colors properly on the chlorine testing strip because he has a color vision deficiency.

As many may know, a chlorine testing kit is a simple devise that a person can use to measure total levels of chlorine, hardness, cyanuric acid, pH, alkalinity, and many other properties of water in a pool. All the individual has to do is dip a test strip into the pool and then observe where the colors on the test strip align to the colors on the accompanying chart (located on the box of the kit). They all look something like this:

chlorine test strip

However, my father would have great difficulty distinguishing between certain colors after removing the test strip from our pool in the backyard, so he would always ask for my assistance. Although I loved doing this job each and every year, I always questioned why my father could not see the differences between the colors. I always just assumed that when he told me that he was “color-blind” he meant that he saw everything in black and white, like in old-school movies.

Consequently, now that I am older and have learned about color vision, I realize that my assumption about my father was incorrect. My father, like 8% of the male population and 0.5% of the female population did in fact have a color vision deficiency, but he did not see in black and white. There are many different types of defects and when I assumed that my father was completely unable to see color, I was assuming he was a cone monochromat or a rod monochromat (neither of which was really the case). Cone monochromats only have one cone type and rod monochromats have no cone of any type, which results in people with these defects being “truly color-blind.” This is because it’s impossible for them to see different wavelengths of light without multiple kinds of photoreceptors and those wavelengths from light reflection is what allows people to see colors in the first place. As it turns out, my father is actually color-anomalous (completely different than the two defects previously discussed), which means that he has two types of cones that are so similar that discriminations cannot be made based on them. In his particular case, he has very similar L-cones and M-cones, which means that he has difficulty differentiating between middle wavelengths and long wavelengths in the electromagnetic spectrum. The middle wavelengths are perceived as the greens and yellows by a majority of people and have wavelengths mostly between 500nm and 600nm. On the other hand, long wavelengths are perceived as the oranges and reds by a majority of people and have wavelengths mostly between 600nm and 700nm. As a result, my father, who has very similar L-cones and M-cones, has trouble telling the difference between green, yellow, orange, and red at times.

In the end, our pool in the backyard was always managed properly and my siblings and I enjoyed swimming just about every day of the summer. Even though my father had difficulty telling the difference between certain colors on the chlorine test strip, I was always able to lend a helping hand and make sure our chlorine, pH, and bromine levels were not too high or too low. I now understand that my father is simply color-anomalous, with similar L-cones and M-cones; he doesn’t actually see in black and white like I always assumed he did when I was a little kid.

Source for picture: http://blog.intheswim.com/beginners-guide-to-pool-water-testing/

“What Color is This?”

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Throughout my life I have been corrected numerous times when stating the color of an object or material. Shades of purple and blue can get mixed up as well as shades of green and red. I am often corrected by my fiancé when picking out new clothing at a store, and there are even times when I have to ask her, “What color is this?” Although it can be frustrating at times admitting that I am wrong and my fiancé is right, this form of colorblindness has not affected me too much in my daily life. Maybe this colorblindness is a reason as to why I often chose neon colors as my favorite because they are the easiest for me to identify?

Unfortunately for my younger sister, this problem has become much more of an obstacle. During this class we have learned that red/green colorblindness can be hereditary and this has proved to be true for her as well. She is in her sophomore year at The United States Air Force Academy and recently found out she is red/green colorblind just like I am. However, she suffered immediate consequences regarding her future in the military. This colorblindness meant that she will never be allowed to pilot an airplane like she had once hoped. Many of the indicator lights in an airplane are small dots of red and green next to each other, so the slightest hesitation in determining them could prove deadly. Although I know this seemed like a huge setback for her at first, I believe she is handling it quite well. As a result of not being able to fly a plane, she has learned to fly her body, and has become an avid skydiver over the last year. She even is planning on helping me earn my skydiving license this summer.

This red/green colorblindness is a result of genetics. When light enters the eye is hits the rods and cones in the retina. The cones are responsible for color vision and contain photo pigments that respond to the amount of light that is hitting them. There are three types of cones in the eye that allow a person to see color when they send signals to the brain together. However, if any of the cones are deficient, then a person will not be able to see a full spectrum of color. My sister and I have most likely both inherited this from our parents due to a bad X chromosome. The difference is that I inherited this from only my mother because as a male I only have one X chromosome. My sister however, has received deficient X chromosomes from both my mother and father because she has two X chromosomes and still is red/green colorblind.

There are many tests to determine if a person is colorblind and the most popular is a dot test. These tests are often available for free online and can help a person gain some insight into their ability to see color. The following website has a free colorblind test for those readers who are interested.

http://enchroma.com/test/instructions/