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Commentary
How Effective are Indicators for Individuals with Color Vision Deficiency?Click to copy article linkArticle link copied!
- Nicholas J. RobertsNicholas J. RobertsChemistry Department, Dalhousie University, Halifax, Nova Scotia B3H 4R2, CanadaMore by Nicholas J. Roberts
- Toren HynesToren HynesChemistry Department, Dalhousie University, Halifax, Nova Scotia B3H 4R2, CanadaMore by Toren Hynes
- Devon StaceyDevon StaceyChemistry Department, Dalhousie University, Halifax, Nova Scotia B3H 4R2, CanadaMore by Devon Stacey
- Jennifer L. MacDonald*Jennifer L. MacDonald*E-mail: [email protected]Chemistry Department, Dalhousie University, Halifax, Nova Scotia B3H 4R2, CanadaMore by Jennifer L. MacDonald
Abstract
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Colored indicators are often used in laboratory courses and academic/industrial research as a qualitative method to test experimental markers. While useful, these tools present challenges to those with color vision deficiency (CVD), who are unable to identify the same results as their peers. Despite this, there is currently a lack of perspective on how individuals with CVD navigate these color-based observations. This commentary presents the perspective of four individuals, three with CVD and one with trichromatic (normal) vision, on how easily colored indicators are identified and how we can address difficulties in a laboratory setting.
This publication is licensed for personal use by The American Chemical Society.
Copyright © 2023 American Chemical Society and Division of Chemical Education, Inc.
Introduction
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With respect to the sciences, there exist two major types of assessment of results: quantitative, which deals with “hard” data; and qualitative, which relies more on reasonable interpretation. (1) Between these two methods, qualitative assessment is generally faster than quantitative and in the context of a laboratory setting may be used as a quick check of results.
In chemistry, observing a color change is among the most popular qualitative assessment methods. Observing color changes is broadly applicable, and can be found in tests including complexometric titrations (2) and gastric content identification. (3) While these methods are indeed useful, they also exclude a substantial portion of the population; namely, those who have color vision deficiency (CVD). (4−7) CVD affects 8.3% of males and 0.5% of females worldwide, where the three main CVD types are protanopia (2.14% of the population), characterized by an insensitivity to red light; deuteranopia (6.45% of the population), characterized by an insensitivity to green light; and tritanopia (0.01% of the population), characterized by an insensitivity to blue light (the remaining 0.2% is made up of other rarer forms of CVD). (4−7) These disorders are not equally common, and as such, it is difficult to have all three major CVD disorders in the same room at the same time.
Many color interpretation methods are not developed with CVD in mind; for example, a common pH paper (Precision Laboratories (8)) found in most chemistry laboratories changes from a bright red color (for a strong acid) to a dark blue color (for a strong base), with intermediate colors in between (orange, yellow, and green). The problem with these color changes is that red, orange, yellow, and green can be very difficult to identify for those with CVD. This is illustrated in Figure 1, which shows three sets of pH tests viewed under trichromatic (i.e., normal color vision), protanopic, deuteranopic, and tritanopic vision. The observed results for those with CVD vary greatly; for example, whereas someone with protanopia might be able to differentiate the strong base against the weak base using the pH paper, someone with deuteranopia would have a much more challenging time completing the same task. This illustrates the inequity that these tests present, even within the same type of disability.
Figure 1
Figure 1. Three sets of tests (universal indicator: pH solution, pH paper, and pH strips) demonstrate the experimental view of individuals with trichromatic, protanopic, deuteranopic, and tritanopic color vision. The images were taken by the authors using a Samsung Galaxy 8 camera under lighting from a Neewer Ring Light (14 in., 36W, 5500K LED). Image filtering was applied to the images using ChromaticVision Simulator (16) to simulate protanopic, deuteranopic, and tritanopic color vision.
Color is a commonly used check-in for students in chemistry programs in order to monitor reaction progress. Experiments such as titrations, the copper cycle, clock reaction, and pH determination all require students to have trichromatic vision to perform equally; however, for those with dichromatic vision, the experiment cannot be performed equitably. The chemical education literature has several articles addressing solutions to this inequity through technology-based approaches that assist individuals with CVD in visualizing color in the laboratory. (9−13) However, there is a gap in said literature with respect to the voices of those with CVD, particularly with respect to what these individuals experience when performing color-based observations.
In this commentary, three methods of color-based assessment were used to interpret the pH of five unknown solutions. The authors (undergraduate/graduate students and faculty) consist of one of each major CVD type: protanopia, deuteranopia, and tritanopia, as well as one with trichromatic vision. We hope that by presenting the authors’ perspectives, we will be able to provide meaningful commentary on qualitative color-based practices taking place in higher education laboratories and beyond, specifically with respect to a hidden/invisible disability like CVD. (14,15)
METHODS AND AUTHOR’S PERSPECTIVE
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Three different universal indicator color-changing methods were used in this experiment: (i) pH solution (ACP Chemicals Inc., Product #: U0165), (17) (ii) pH paper (Precision Laboratories, VWR Catalog #: 60775–000), (8) and (iii) pH strips (ColorpHast pH Strips, Item #: 1.9535.0007). (18) Of these, the pH strips provide color with pattern-based observables to assign pH, whereas the pH solution and pH paper only provide color as the observable to assign pH.
The authors were presented with five numbered aqueous unknown solutions: a strong acid (0.1 M HCl), a weak acid (0.1 M CH3COOH), a neutral species (0.1 M NaCl), a weak base (0.1 M NH3), and a strong base (0.1 M NaOH). They were then asked to discern which unknown number corresponds to which unknown solution using the three methods outlined above.
The authors did not discuss their thoughts about these tests until they had written them independently. This was to ensure that their perspectives were not influenced by one another. When all of the authors had finished writing their independent sections, they were combined and formatted to create a single article.
In the following sections, each author describes their experience of unknown identification via color perception using pH solution, pH paper, and pH strips. Figures 2–5 show the differences in colors viewed by each author due to their color vision type to provide context to the author’s written descriptions.
Figure 2
Figure 2. Three sets of tests (universal indicator: pH solution, pH paper, and pH strips) demonstrate experimental views of an individual with trichromatic vision.
Experience of Author with Trichromatic Vision
With respect to this set of tests, this is what the trichromatic author reported:
Universal Indicator pH Solution
I found that the pH solution was the fastest method to determine the pH of the unknown solutions. I was able to independently distinguish all 5 colors and correctly identify the unknown solutions; however, I did need to add additional indicator to the wells of the spot plate to improve the resolution of colors between the strong acid (red) and the weak acid (orange) as well as the strong base (purple) and weak base (blue).
Universal Indicator pH Paper
I found this method to be less reliable than the pH solution to determine the pH of the unknown solutions. I was able to correctly identify the solutions; however, I did find distinguishing the strong base (blue) from the weak base (blue-green) from neutral to be more challenging. When the pH paper was wet, the strong base and weak base appeared nearly identical (blue), but I was able to assign all of the others. When the papers dried, the strong base pH paper remained blue and then the weak base appeared more of a light yellow-green, more similar to the yellow color of the neutral. Ultimately, though, I was able to independently determine the correct result without retesting.
Universal Indicator pH Strips
I found these to be easy to use; however, at first it took me longer to get used to interpreting the color code/pattern which corresponded to each pH on the legend. Once I became accustomed to the color code comparison, I was able to identify all of the unknowns without retesting and without any potential “close call” resolution issues. The pH strips had an advantage of being nonbleed so that they could be used without contaminating solution and without significant amounts of solution fractioning (which is required for pH solution and pH paper). I could quickly see the benefit of these pH strips for a variety of types of color vision. The Universal Design for Learning (UDL) and communicating data with color literature (19−25) note that color alone should not be the only means of communicating data. It is recommended, for example, when designing slides, figures, and maps to incorporate labels or patterns in addition to color to ensure that the information is communicated/interpreted equitably by the reader. Thus, the pH strips, providing stacked blocks of color created not only a mode of color-based identification but also a mode of pattern-based identification, making the pH strips the more accessible and equitable option from the options we tested.
Summarized thoughts: The trichromatic authors noted that the fastest method for them was the pH solution. The least reliable method was the pH paper, citing difficulties with identification of the neutral, weak base, and strong base solutions. The author had difficulty initially acclimating to the pH strips legend but thought these were the most accessible of the three choices (Figure 2).
Experience of Author with Dichromatic Vision: Protanopia
With respect to this set of tests, this is what the protanopic author reported:
Universal Indicator pH Solution
A qualitative description of colors (as provided in the lab manual) is essentially meaningless if your color vision is not normal. A color that is supposedly “red” can look brown or black, depending on the shade, pink can be gray or light blue, and purple cannot be distinguished from dark blue. To sum up my findings: the strong and weak bases (solutions one and five) are essentially impossible to distinguish, and both looked dark blue. However, seeing that a pink color can look blue or even gray to me and that one and five were the most intensely color solutions, I thought they were the strong acid and base. Solution two looked like a weak acid and was dark yellow/light orange. Solution three looked blue-green; therefore, I figured it was neutral. Solution four was light blue; therefore, a weak base seemed correct. There is a chance that I might have performed better on this test if there were color photographs of solutions at each pH included in the lab manual. That being said, sometimes colors can look different in a photograph than they do in reality. The exact appearance of color in a photograph depends on the camera used to take the picture, the lighting used when the photograph was taken, and the color gamut of the monitor used to display the picture. (26,27) If the image is printed, the color range of the printer can also affect what you see on paper.
Universal Indicator pH Paper
Not much better than the solution, and the actual colors of the papers do not correspond especially well to what’s printed on the package. One and five essentially looked the same; I went with strong base for one and strong acid for five, based on what I remember regarding the paper’s texture: more of the background yellow shows through in bases than acids, because strong bases tend to cause the indicator to bleed out more than strong acids. Two looked like a weak acid. Three I did not know. By deduction, it should have been a weak base, but it did not exactly look right. Four was neutral as it did not look like anything other than wet paper. Regardless of one’s color vision, these papers must be compared to the scale when they’re wet. Once they dry out (after ∼ five minutes), their colors fade, and assessment becomes meaningless. Unfortunately, this is not stated clearly in either the lab manual or on the bottles of pH paper.
Universal Indicator pH Strips
Very fast and easy to use. No confusion whatsoever. These are what I personally use in lab. These should be used for all undergraduate laboratories where determining pH is required. These strips are great, not just because the colors are easily distinguishable, but because it is possible to compare the pattern seen on the pH strips with that given on the box, which further reduces the opportunities for confusion.
Summarized thoughts: The author had difficulties using both the pH solution and the pH paper, particularly with differentiating the strong/weak bases. Of the three methods, the pH strips were preferred as both the fastest and most reliable method (Figure 3).
Figure 3
Figure 3. Three sets of tests (universal indicator: pH solution, pH paper, and pH strips) demonstrate the experimental view of an individual with protanopic color vision.
Experience of Author with Dichromatic Vision: Deuteranopia
With respect to this set of tests, this is what the deuteranopic author reported:
Universal Indicator pH Solution
For the pH solution and spot plate combination, the way I interpreted results varied quite a bit based on the background color, i.e., what color surface the spot plate was on. For darker surfaces, it was quite difficult to differentiate between some of the darker colors on top of the ones that I have difficulty seeing. If the background was too light, I found it difficult to differentiate the lighter colors. If the background was appropriate, i.e., if it was such that both the lighter and darker colors had sufficient contrast, I would consider the pH solution passable. That being said, I would prefer not to have to rely on background AND indicator colors to make my observations in lab.
Universal Indicator pH Paper
The pH papers I find very difficult to use, where reds and oranges look almost identical regardless of background color and being able to discern a neutral or slightly basic/acidic substance is out of the question. The pH paper also bleeds their color out, adding another layer of difficulty to trying to discern what the pH of my solution is. These were both temperamental and unhelpful – I would not use these if given the choice to use anything else.
Universal Indicator pH Strips
Out of all three, the pH strips were incredibly useful. I do not think I’ve ever been able to assess pH as quickly as I was able to with the pH strips. There is less emphasis on color with them, and more so on recognizing a pattern, so that even if I cannot see one color, I can still make a proper assessment of the pH of my solution. The other two rely heavily on normal color vision, and I found them quite temperamental. On the whole, I would love to be able to use the pH strips again in all aspects of qualitative chemistry assessment.
Summarized thoughts: The deuteranopic author found the pH solution dependent on background color, and the pH papers unreasonable to use. The pH strips were the fastest and preferred methods of assessment (Figure 4).
Figure 4
Figure 4. Three sets of tests (universal indicator: pH solution, pH paper, and pH strips) demonstrating experimental view of an individual with deuteranopic color vision.
Experience of Author with Dichromatic Vision: Tritanopia
With respect to this set of tests, this is what the tritanopic author reported:
Universal Indicator pH Solution
This test is extremely difficult to use effectively when you cannot identify colors across multiple ranges. Unknowns one and five appeared identical, as they were both a clear purple solution and were therefore basic. Unknowns two and three also appeared identical as acids, although I could not assign a weak or strong status to either. Unknown four was clearly neutral or a weak base as it was clear and either blue or green, but again I could not be sure which to choose because of the color range. Overall, I found the pH solution to be useful for distinguishing acids from neutrals and bases; however, the color changed over time: no difference between strong/weak acids or strong/weak bases at first, then no difference between neutral/base and what originally presented as a clear base.
Universal Indicator pH Paper
The first pH paper (strong base) appeared to work well, but the second and fourth pH papers were difficult to differentiate from one another, as neither appeared to change much other than looking a little damp. The third pH paper was clearly identifiable as a strong acid because of the immediate, concentrated red pigment. The fifth pH paper (I thought this was a strong base) looked similar enough to the first paper not to warrant a distinction between them in my final answer. I found the pH paper to be useful for identifying strong acids; however, the color scheme of the legend is not ideal for distinction between strong/weak bases, the solution bled through every paper, the blue/green color was difficult to differentiate, and the pH paper changed color over time. Unknowns one and five appeared to be strong bases at first, and unknowns two and four appeared neutral, then pH paper one bled to yield a white center while pH papers two, four, and five all looked neutral. Overall, the messiest test.
Universal Indicator pH Strips
After the first pH strip came into contact with the first unknown, I immediately knew that I could identify the pH based on the legend provided; there was a strong color contrast between the squares themselves on the strip, which made it significantly easier and faster to compare the strip with the legend. By the time I had dispensed each unknown onto its own respective pH strip, I could clearly and quickly assign four of the unknowns to their correct categories, with only one square on one pH strip producing some doubt or confusion. This was mostly due to my perception of what constitutes a strong or weak acid in terms of pH and had less to do with the subtle difference between the two close pink shades. Overall, I found the pH strip legend easy to identify, with a comprehensive color scheme, no dye bleeding, and less change over time compared to the pH paper and pH solution. However, it was slightly difficult to differentiate between weak and strong acids due to the pink hues being close to one another, but that was mostly user error.
Summarized thoughts: The tritanopic author had difficulty using the pH solution and pH paper, only being able to identify the strong acid with confidence. The pH strips were more helpful, but there was some initial difficulty in understanding the legend to identify their results (Figure 5).
Figure 5
Figure 5. Three sets of tests (universal indicator: pH solution, pH paper, and pH strips) demonstrate an experimental view of an individual with tritanopic color vision.
Summary
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To summarize, while the trichromatic author had no issue using two of the three methods (pH solution and pH strips), all three CVD authors had difficulty when using the pH papers or pH solution. The author with tritanopia noted some issues when initially using the pH strips but still preferred this method compared to the other two.
Discussion
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From this informal assessment, the most popular choice overall was the pH strips. While effective, they are also the most expensive option in this roundup, where approximate costs (in Canadian currency) per test are 6 cents for pH paper, 13 cents for pH solution, and 47 cents for pH strips. This begs several interesting questions: do we deal with a more expensive upfront cost that is most inclusive, do we continue to use what is affordable, or do we seek a middle ground?
The population of CVD individuals within a given classroom is not consistent over many years; i.e., there is variation in the degree of support required. This is not to discourage the implementation of such supports; rather, it is meant to encourage viewing modifications to classroom content through the lens of UDL, (19,20,22) which demonstrates that supports instructors create are working toward more inclusive learning course-wide. In the framework of creating an accessible lab environment, it would be ideal to always choose the more inclusive or the most expensive option. This is not always possible to implement, however, due to the increase in cost in larger classrooms. It is, however, certainly possible to make this more inclusive option available for those that need it, i.e., making the support available but not mandatory for use course-wide. In addition, careful consideration of the colors that an experiment may present─and how those colors are perceived by those with CVD─can help instructors identify where to implement specific supports. This can help to lower the cost. For example, all authors were generally able to identify whether a solution was strongly basic or acidic in the tests performed, and this may be all that is required for the lesson.
Alternatively, instructors may be interested in modifying the experiment outright. This is an excellent idea if an instructor has the time and resources to do so; however, oftentimes, this is impossible to do. In such cases, the instructor might consider the following approaches: improving contrast by changing viewing backgrounds (28,29) or increasing solution-based indicator amounts (where impact to experimental outcomes is minimal). High-contrast backgrounds help by increasing color contrast in the foreground, i.e., colors become easier to differentiate with the appropriate background. Qualitatively, the deuteranopic author’s perspective aligns with this when discussing the pH solution. Increasing indicator amount increases the concentration, which again increases contrast between other colors as well as the background. These suggestions cost very little to implement in a classroom setting and can be quite effective at helping those students in need of support(s).
Incorporation of these potential modifications into laboratory manuals and standard operating procedures is another way to create awareness while supporting those who may need assistance. For example, if the reader has trichromatic vision, applying CVD filters (16,30,31) and considering/simulating color palettes (28,29,32) can help to highlight areas where students with CVD may struggle and allow pre-emptive planning of support content for color-based interpretations. If the reader is teaching within a team, communicate the importance of support for students and colleagues by tailoring teaching support content for them where possible. For example, making mention of common CVD issues during TA training sessions, providing CVD simulations of the experiment, and providing insight into potential experimental modifications can help to achieve this goal.
It is important to emphasize that implementing or creating CVD supports does not alter learning outcomes for students; rather, these implementations are meant to improve the equity of the material being learned by students. Learning outcomes are not dependent on the identification of a color but are dependent on what the interpretation of that color means. Thus, if students cannot identify a color correctly, their interpretation cannot be fairly assessed.
We would like more institutions to consider implementing CVD support in their programs. While small, individuals with CVD still make up 8.8% of the population, which, in our eyes, is substantial enough to warrant adding more support. We hope that by spreading awareness of this often-overlooked issue more people will consider adding these supports to their places of work/learning. If we truly wish to have everyone perform the same experiment, then support should be put in place such that everyone truly can perform the same experiment.
Author Information
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- Jennifer L. MacDonald - Chemistry Department, Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada;
https://orcid.org/0000-0002-8959-8648;
- Nicholas J. Roberts - Chemistry Department, Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada;https://orcid.org/0000-0002-4989-8726
Acknowledgments
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The authors wish to acknowledge their past/present students in Chem 1011/1012 and Chem 1021/1022 and the First Year Lab Teaching Team for their conversation/feedback surrounding the use of indicators in our laboratory. The authors would like to extend their gratitude towards Dr. Gianna Aleman Milán and Dr. Saurabh Chitnis for their helpful feedback on the manuscript. The authors are also grateful for the financial support of Dalhousie University, and the Department of Chemistry for the indicators and materials.
References
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This article references 32 other publications.
- 1Joint Task Force Transformation Initiative. Guide for Conducting Risk Assessments, 0 ed.; NIST SP 800–30r1; National Institute of Standards and Technology: Gaithersburg, MD, 2012; p NIST SP 800–30r1. DOI: 10.6028/NIST.SP.800-30r1Google ScholarThere is no corresponding record for this reference.
- 2Lyle, S. J.; Rahman, Md. M. Complexometric Titration of Yttrium and the Lanthanons─I: A Comparison of Direct Methods. Talanta 1963, 10 (11), 1177– 1182, DOI: 10.1016/0039-9140(63)80170-8Google Scholar2https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaF3sXkslyjtrg%253D&md5=0727ea408975c3a522bf1963fad16439Complexometric titration of yttrium and the lanthanons. I. A comparison of direct methodsLyle, S. J.; Rahman, Md. M.Talanta (1963), 10 (11), 1177-82CODEN: TLNTA2; ISSN:0039-9140.A comparison is made of a no. of direct complexometric titrations previously published for the detn. of Y and the lanthanons. Working and optimum pH ranges are obtained for what are considered to be the best indicators, Alizarin Red S screened with methylene blue, Eriochrome Black T, coppernaphthyl azoxine, and Xylenol Orange. The precision and accuracy of the selected methods are detd. by carrying out replicate titrations on standard solns, of CeIII Y, and Yb. The results, together with addnl. observations made on the behavior of indicators in the different methods, suggest that Xylenol Orange at pH 5.8-6.4 is most satisfactory and convenient for direct titrations.
- 3Chaffe, A. Which pH Paper?. British Journal of Anaesthesia 1987, 59 (9), 1189– 1191, DOI: 10.1093/bja/59.9.1189Google Scholar3https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A280%3ADyaL1c%252FisVKhug%253D%253D&md5=19d3e64cc4c08e901d8039c40001a6f1Which pH paper?Chaffe ABritish journal of anaesthesia (1987), 59 (9), 1189-91 ISSN:0007-0912.Five different brands of pH indicator paper were used by 20 anaesthetists to test four buffer solutions. There were significantly fewer correct answers with two papers than with the other three. The worst paper in the study (Whatman full range) gave only 20% correct answers, compared with 92.5% from the best (Merck).
- 4McIntyre, D. Colour Blindness: Causes and Effects; Dalton Publishing: Chester, 2002; pp 34– 38.Google ScholarThere is no corresponding record for this reference.
- 5Willis, L. A Brief Guide To Colour Blindness: All the Important Things That You Need to Know about Colour Blindness. Independently Published, 2019; pp 7– 17.Google ScholarThere is no corresponding record for this reference.
- 6Colour Blind Awareness. Colour Blind Awareness. https://www.colourblindawareness.org/ (accessed Apr 2023).Google ScholarThere is no corresponding record for this reference.
- 7Hansen, E. What Is Color Blindness?: What to Know If You’re Diagnosed With Color Blindness; CreateSpace Independent Publishing Platform, 2013; pp 19– 23.Google ScholarThere is no corresponding record for this reference.
- 8pH Test Strips, Precision Laboratories. VWR. https://ca.vwr.com/store/product/en/4644396/ph-test-strips-precision-laboratories (accessed Apr 2023).Google ScholarThere is no corresponding record for this reference.
- 9Bandyopadhyay, S.; Rathod, B. B. The Sound and Feel of Titrations: A Smartphone Aid for Color-Blind and Visually Impaired Students. J. Chem. Educ. 2017, 94 (7), 946– 949, DOI: 10.1021/acs.jchemed.7b00027Google Scholar9https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2sXptFaqu70%253D&md5=8fdfe5393df47fcfc5fa21f7cef83402The Sound and Feel of Titrations: A Smartphone Aid for Color-Blind and Visually Impaired StudentsBandyopadhyay, Subhajit; Rathod, Balraj B.Journal of Chemical Education (2017), 94 (7), 946-949CODEN: JCEDA8; ISSN:0021-9584. (American Chemical Society and Division of Chemical Education, Inc.)An Android-based application has been developed to provide color-blind and visually impaired students a multisensory perception of color change obsd. in a titrn. The application records and converts the color information into beep sounds and vibration pulses, which are generated by the smartphone. It uses a range threshold of hue and satn. coordinates of the HSV (hue, satn., value) color space for detecting a color change specific to an indicator for, e.g., shades of pink for phenolphthalein-based titrn., and informs the users before and upon attaining the end point. This approach can enable color-blind and visually impaired students to actively perform a fairly routine lab. activity of titrn.
- 10Wright, C. E. Leveraging an App to Support Students with Color-Vision Deficiency and Color-Blindness in Online General Chemistry Laboratories. J. Chem. Educ. 2022, 99 (3), 1149– 1154, DOI: 10.1021/acs.jchemed.1c00664Google Scholar10https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BB38XjsFGrsbY%253D&md5=cc107c463ea47ef4da4c8f07fad55475Leveraging an App to Support Students with Color-Vision Deficiency and Colorblindness in Online General Chemistry LaboratoriesWright, Casey ElizabethJournal of Chemical Education (2022), 99 (3), 1149-1154CODEN: JCEDA8; ISSN:0021-9584. (American Chemical Society and Division of Chemical Education, Inc.)Assistive technologies remain important in supporting student learning in both in-person labs. and the online lab. environment. In this article we describe an adaptation of a smart phone technol. called the Color Blind Pal App to aid students in complementing online lab. assignments in a general chem. course. The app was integrated into three online lab. expts. to help students collect data from simulated flame tests, at. emission spectra, pptn. reactions, and colorimetric titrns. We share how incorporating the app has influenced our perspective on inclusive practices in the online lab curriculum as the app allows both users with color vision deficiencies or color-blindness to make color observations and for instructors to simulate color-vision deficiencies when designing curricula. Given our use of the app as an assistive technol., we discuss implications for a shift toward Universal Design for Learning (UDL) to proactively design inclusive online lab. curricula.
- 11Qutieshat, A.; Aouididi, R.; Arfaoui, R. Design and Construction of a Low-Cost Arduino-Based PH Sensor for the Visually Impaired Using Universal PH Paper. J. Chem. Educ. 2019, 96 (10), 2333– 2338, DOI: 10.1021/acs.jchemed.9b00450Google Scholar11https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1MXhslaitL3P&md5=db72b25dd8c0fa7877faf35b4820bb9fDesign and Construction of a Low-Cost Arduino-Based pH Sensor for the Visually Impaired Using Universal pH PaperQutieshat, Abubaker; Aouididi, Rayhana; Arfaoui, RayanJournal of Chemical Education (2019), 96 (10), 2333-2338CODEN: JCEDA8; ISSN:0021-9584. (American Chemical Society and Division of Chemical Education, Inc.)A review. This technol. report outlines the design and construction of a simple Arduino-based pH sensor using universal pH paper; it can be assembled for less than $40 and is ideal for use in lab. classrooms teaching students with visual disabilities. The device is simple to construct and suitable for adoption in school chem. labs. because of its miniature size, user-friendliness, and flexible coding. The Arduino-based pH sensor allows the visually impaired to use and interpret universal pH paper in measuring pH, which could not be previously attempted. A change in color of the indicator paper, as detected by the RGB color sensor, generates a distinctive audible tone that corresponds to the pH value being measured. This device can function as a helping hand in the learning process by facilitating a more exciting and meaningful lab. exercise experience not only for the visually impaired but also for their normal-sighted peers.
- 12Bettenhausen, C. Experimenting with EnChroma’s Color-Blind Assistance Glasses. C&EN Global Enterp 2017, 95 (6), 80– 80, DOI: 10.1021/cen-09506-newscriptsGoogle ScholarThere is no corresponding record for this reference.
- 13Li, J.; O’Neill, M. L.; Pattison, C.; Zhou, J. H.-W.; Ito, J. M.; Wong, C. S. T.; Yu, H.-Z.; Merbouh, N. Mobile App to Quantify PH Strips and Monitor Titrations: Smartphone-Aided Chemical Education and Classroom Demonstrations. J. Chem. Educ. 2023, 100, 3634, DOI: 10.1021/acs.jchemed.3c00227Google Scholar13https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BB3sXhs12lsrbN&md5=b333498fa0ae41ef2e1d7dd97b1f4015Mobile app to quantify pH strips and monitor titrations: smartphone-aided chemical education and classroom demonstrationsLi, Jiaxing; ONeill, Marissa L.; Pattison, Connor; Zhou, James H-W.; Ito, Joshua M.; Wong, Calvin S. T.; Yu, Hua-Zhong; Merbouh, NabylJournal of Chemical Education (2023), 100 (9), 3634-3640CODEN: JCEDA8; ISSN:0021-9584. (American Chemical Society and Division of Chemical Education, Inc.)PH detn. and acid-base titrns. are essential expts. performed by high school and university undergraduate students alike throughout their chem. education. While these expts. often rely on conventional pH meters for quantification and pH test strips or indicators for qual. assessments, we demonstrated herein that a smartphone-based pH detn. technique, performing digital image anal., particularly the detn. of either the dominant wavelength or the RGB intensities, could readily replace all but one conventional pH meter in a classroom setting. Using an inhouse developed smartphone-based pH reading application (app), students were able to det. the pH and perform titrns. using pH strips and universal indicators, producing results matching those detd. with a std. pH meter. The application and its "variants" are available for download (https://tinyurl.com/2dashjyk & https://tinyurl.com/4d73wnxt) and no prior knowledge of coding or programing was required from the students. All that was needed was an Android 11 phone or tablet with an Internet connection. Moreover, the students and instructors' reactions to the mobile app alike were very pos. and showcased the need and interest for such inexpensive technol., which allows for the running of an entire class for pH detn. of multiple real-life samples or acid/base titrn. without using std. pH meters.
- 14Sweet, C. Hidden or Invisible Disabilities and Laboratory Accommodations. In Accessibility in the Laboratory; ACS Symposium Series; American Chemical Society, 2018; Vol. 1272, pp 69– 75. DOI: 10.1021/bk-2018-1272.ch005Google ScholarThere is no corresponding record for this reference.
- 15British Journal of Nursing - Colour vision deficiency: the ‘unseen’ disability. British Journal of Nursing. https://www.britishjournalofnursing.com/content/clinical/colour-vision-deficiency-the-unseen-disability/ (accessed Aug 2023).Google ScholarThere is no corresponding record for this reference.
- 16Chromatic Vision Simulator > Home. https://asada.website/cvsimulator/e/ (accessed Apr 2023).Google ScholarThere is no corresponding record for this reference.
- 17Online Catalogue. ACP Chemicals Inc.. https://www.acpchem.com/e/catalogue-public.asp?qNewOffset=301&qCategoryCode=16 (accessed Apr 2023).Google ScholarThere is no corresponding record for this reference.
- 18Thermal Scientific. https://www.thermalscientific.com/product/3211/suppliers/emd-millipore-corporation/colorphast-ph-strips-emd-millipore (accessed Apr 2023).Google ScholarThere is no corresponding record for this reference.
- 19The UDL Guidelines. UDL. https://udlguidelines.cast.org/ (accessed Aug 2023).Google ScholarThere is no corresponding record for this reference.
- 20Meeks, L. M.; Jain, N. R.; Herzer, K. R. Universal Design: Supporting Students With Color Vision Deficiency (CVD) in Medical Education. Journal of Postsecondary Education and Disability 2016, 29 (3), 303– 309Google ScholarThere is no corresponding record for this reference.
- 21Communicating data with colour. Victorian Government Department of Planning and Community Development. https://www.planning.vic.gov.au/guides-and-resources/guides/all-guides/communicating-data-with-colour (accessed Aug 2023).Google ScholarThere is no corresponding record for this reference.
- 22Scanlon, E.; Legron-Rodriguez, T.; Schreffler, J.; Ibadlit, E.; Vasquez, E.; Chini, J. J. Postsecondary Chemistry Curricula and Universal Design for Learning: Planning for Variations in Learners’ Abilities, Needs, and Interests. Chem. Educ. Res. Pract. 2018, 19 (4), 1216– 1239, DOI: 10.1039/C8RP00095FGoogle ScholarThere is no corresponding record for this reference.
- 23Prieto, L. R.; Siegel, Z. D.; Kaiser, D. J. One Fish, Two Fish; Red Fish (or Green Fish?): Assisting Students With Color Vision Deficiency. Teaching of Psychology 2021, 48 (1), 90– 94, DOI: 10.1177/0098628320959946Google ScholarThere is no corresponding record for this reference.
- 24Color and Universal Design. UXmatters. https://www.uxmatters.com/mt/archives/2021/09/color-and-universal-design.php (accessed Aug 2023).Google ScholarThere is no corresponding record for this reference.
- 25Color Universal Design Handbook. Color Universal Design Organization, Tokyo . 2006. https://webcube-general.s3.amazonaws.com/eizo/media/contentassets/2015/10/09/handbook.pdf (accessed Aug 2023).Google ScholarThere is no corresponding record for this reference.
- 26Why Do Colors Look Different on Computer Monitors & Screens? Quality Logo Products. https://www.qualitylogoproducts.com/promo-university/why-monitors-display-different-colors.htm (accessed Apr 2023).Google ScholarThere is no corresponding record for this reference.
- 27Why don’t colors look the same across different devices? BenQ. https://www.benq.com/en-us/knowledge-center/knowledge/why-dont-colors-look-the-same-across-different-devices.html (accessed Apr 2023).Google ScholarThere is no corresponding record for this reference.
- 28WebAIM: Contrast Checker. https://webaim.org/resources/contrastchecker/ (accessed Apr 2023).Google ScholarThere is no corresponding record for this reference.
- 29Colour Contrast Analyzer. TPGi. https://www.tpgi.com/color-contrast-checker/ (accessed Aug 2023).Google ScholarThere is no corresponding record for this reference.
- 30Coblis ─ Color Blindness Simulator. Colblindor. https://www.color-blindness.com/coblis-color-blindness-simulator/ (accessed Apr 2023).Google ScholarThere is no corresponding record for this reference.
- 31Color Oracle. https://colororacle.org/ (accessed Aug 2023).Google ScholarThere is no corresponding record for this reference.
- 32Nichols, D. Coloring for Colorblindness. http://www.davidmathlogic.com/colorblind/ (accessed Apr 2023).Google ScholarThere is no corresponding record for this reference.
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Abstract
Figure 1
Figure 1. Three sets of tests (universal indicator: pH solution, pH paper, and pH strips) demonstrate the experimental view of individuals with trichromatic, protanopic, deuteranopic, and tritanopic color vision. The images were taken by the authors using a Samsung Galaxy 8 camera under lighting from a Neewer Ring Light (14 in., 36W, 5500K LED). Image filtering was applied to the images using ChromaticVision Simulator (16) to simulate protanopic, deuteranopic, and tritanopic color vision.
Figure 2
Figure 2. Three sets of tests (universal indicator: pH solution, pH paper, and pH strips) demonstrate experimental views of an individual with trichromatic vision.
Figure 3
Figure 3. Three sets of tests (universal indicator: pH solution, pH paper, and pH strips) demonstrate the experimental view of an individual with protanopic color vision.
Figure 4
Figure 4. Three sets of tests (universal indicator: pH solution, pH paper, and pH strips) demonstrating experimental view of an individual with deuteranopic color vision.
Figure 5
Figure 5. Three sets of tests (universal indicator: pH solution, pH paper, and pH strips) demonstrate an experimental view of an individual with tritanopic color vision.
References
This article references 32 other publications.
- 1Joint Task Force Transformation Initiative. Guide for Conducting Risk Assessments, 0 ed.; NIST SP 800–30r1; National Institute of Standards and Technology: Gaithersburg, MD, 2012; p NIST SP 800–30r1. DOI: 10.6028/NIST.SP.800-30r1There is no corresponding record for this reference.
- 2Lyle, S. J.; Rahman, Md. M. Complexometric Titration of Yttrium and the Lanthanons─I: A Comparison of Direct Methods. Talanta 1963, 10 (11), 1177– 1182, DOI: 10.1016/0039-9140(63)80170-82https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaF3sXkslyjtrg%253D&md5=0727ea408975c3a522bf1963fad16439Complexometric titration of yttrium and the lanthanons. I. A comparison of direct methodsLyle, S. J.; Rahman, Md. M.Talanta (1963), 10 (11), 1177-82CODEN: TLNTA2; ISSN:0039-9140.A comparison is made of a no. of direct complexometric titrations previously published for the detn. of Y and the lanthanons. Working and optimum pH ranges are obtained for what are considered to be the best indicators, Alizarin Red S screened with methylene blue, Eriochrome Black T, coppernaphthyl azoxine, and Xylenol Orange. The precision and accuracy of the selected methods are detd. by carrying out replicate titrations on standard solns, of CeIII Y, and Yb. The results, together with addnl. observations made on the behavior of indicators in the different methods, suggest that Xylenol Orange at pH 5.8-6.4 is most satisfactory and convenient for direct titrations.
- 3Chaffe, A. Which pH Paper?. British Journal of Anaesthesia 1987, 59 (9), 1189– 1191, DOI: 10.1093/bja/59.9.11893https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A280%3ADyaL1c%252FisVKhug%253D%253D&md5=19d3e64cc4c08e901d8039c40001a6f1Which pH paper?Chaffe ABritish journal of anaesthesia (1987), 59 (9), 1189-91 ISSN:0007-0912.Five different brands of pH indicator paper were used by 20 anaesthetists to test four buffer solutions. There were significantly fewer correct answers with two papers than with the other three. The worst paper in the study (Whatman full range) gave only 20% correct answers, compared with 92.5% from the best (Merck).
- 4McIntyre, D. Colour Blindness: Causes and Effects; Dalton Publishing: Chester, 2002; pp 34– 38.There is no corresponding record for this reference.
- 5Willis, L. A Brief Guide To Colour Blindness: All the Important Things That You Need to Know about Colour Blindness. Independently Published, 2019; pp 7– 17.There is no corresponding record for this reference.
- 6Colour Blind Awareness. Colour Blind Awareness. https://www.colourblindawareness.org/ (accessed Apr 2023).There is no corresponding record for this reference.
- 7Hansen, E. What Is Color Blindness?: What to Know If You’re Diagnosed With Color Blindness; CreateSpace Independent Publishing Platform, 2013; pp 19– 23.There is no corresponding record for this reference.
- 8pH Test Strips, Precision Laboratories. VWR. https://ca.vwr.com/store/product/en/4644396/ph-test-strips-precision-laboratories (accessed Apr 2023).There is no corresponding record for this reference.
- 9Bandyopadhyay, S.; Rathod, B. B. The Sound and Feel of Titrations: A Smartphone Aid for Color-Blind and Visually Impaired Students. J. Chem. Educ. 2017, 94 (7), 946– 949, DOI: 10.1021/acs.jchemed.7b000279https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2sXptFaqu70%253D&md5=8fdfe5393df47fcfc5fa21f7cef83402The Sound and Feel of Titrations: A Smartphone Aid for Color-Blind and Visually Impaired StudentsBandyopadhyay, Subhajit; Rathod, Balraj B.Journal of Chemical Education (2017), 94 (7), 946-949CODEN: JCEDA8; ISSN:0021-9584. (American Chemical Society and Division of Chemical Education, Inc.)An Android-based application has been developed to provide color-blind and visually impaired students a multisensory perception of color change obsd. in a titrn. The application records and converts the color information into beep sounds and vibration pulses, which are generated by the smartphone. It uses a range threshold of hue and satn. coordinates of the HSV (hue, satn., value) color space for detecting a color change specific to an indicator for, e.g., shades of pink for phenolphthalein-based titrn., and informs the users before and upon attaining the end point. This approach can enable color-blind and visually impaired students to actively perform a fairly routine lab. activity of titrn.
- 10Wright, C. E. Leveraging an App to Support Students with Color-Vision Deficiency and Color-Blindness in Online General Chemistry Laboratories. J. Chem. Educ. 2022, 99 (3), 1149– 1154, DOI: 10.1021/acs.jchemed.1c0066410https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BB38XjsFGrsbY%253D&md5=cc107c463ea47ef4da4c8f07fad55475Leveraging an App to Support Students with Color-Vision Deficiency and Colorblindness in Online General Chemistry LaboratoriesWright, Casey ElizabethJournal of Chemical Education (2022), 99 (3), 1149-1154CODEN: JCEDA8; ISSN:0021-9584. (American Chemical Society and Division of Chemical Education, Inc.)Assistive technologies remain important in supporting student learning in both in-person labs. and the online lab. environment. In this article we describe an adaptation of a smart phone technol. called the Color Blind Pal App to aid students in complementing online lab. assignments in a general chem. course. The app was integrated into three online lab. expts. to help students collect data from simulated flame tests, at. emission spectra, pptn. reactions, and colorimetric titrns. We share how incorporating the app has influenced our perspective on inclusive practices in the online lab curriculum as the app allows both users with color vision deficiencies or color-blindness to make color observations and for instructors to simulate color-vision deficiencies when designing curricula. Given our use of the app as an assistive technol., we discuss implications for a shift toward Universal Design for Learning (UDL) to proactively design inclusive online lab. curricula.
- 11Qutieshat, A.; Aouididi, R.; Arfaoui, R. Design and Construction of a Low-Cost Arduino-Based PH Sensor for the Visually Impaired Using Universal PH Paper. J. Chem. Educ. 2019, 96 (10), 2333– 2338, DOI: 10.1021/acs.jchemed.9b0045011https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1MXhslaitL3P&md5=db72b25dd8c0fa7877faf35b4820bb9fDesign and Construction of a Low-Cost Arduino-Based pH Sensor for the Visually Impaired Using Universal pH PaperQutieshat, Abubaker; Aouididi, Rayhana; Arfaoui, RayanJournal of Chemical Education (2019), 96 (10), 2333-2338CODEN: JCEDA8; ISSN:0021-9584. (American Chemical Society and Division of Chemical Education, Inc.)A review. This technol. report outlines the design and construction of a simple Arduino-based pH sensor using universal pH paper; it can be assembled for less than $40 and is ideal for use in lab. classrooms teaching students with visual disabilities. The device is simple to construct and suitable for adoption in school chem. labs. because of its miniature size, user-friendliness, and flexible coding. The Arduino-based pH sensor allows the visually impaired to use and interpret universal pH paper in measuring pH, which could not be previously attempted. A change in color of the indicator paper, as detected by the RGB color sensor, generates a distinctive audible tone that corresponds to the pH value being measured. This device can function as a helping hand in the learning process by facilitating a more exciting and meaningful lab. exercise experience not only for the visually impaired but also for their normal-sighted peers.
- 12Bettenhausen, C. Experimenting with EnChroma’s Color-Blind Assistance Glasses. C&EN Global Enterp 2017, 95 (6), 80– 80, DOI: 10.1021/cen-09506-newscriptsThere is no corresponding record for this reference.
- 13Li, J.; O’Neill, M. L.; Pattison, C.; Zhou, J. H.-W.; Ito, J. M.; Wong, C. S. T.; Yu, H.-Z.; Merbouh, N. Mobile App to Quantify PH Strips and Monitor Titrations: Smartphone-Aided Chemical Education and Classroom Demonstrations. J. Chem. Educ. 2023, 100, 3634, DOI: 10.1021/acs.jchemed.3c0022713https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BB3sXhs12lsrbN&md5=b333498fa0ae41ef2e1d7dd97b1f4015Mobile app to quantify pH strips and monitor titrations: smartphone-aided chemical education and classroom demonstrationsLi, Jiaxing; ONeill, Marissa L.; Pattison, Connor; Zhou, James H-W.; Ito, Joshua M.; Wong, Calvin S. T.; Yu, Hua-Zhong; Merbouh, NabylJournal of Chemical Education (2023), 100 (9), 3634-3640CODEN: JCEDA8; ISSN:0021-9584. (American Chemical Society and Division of Chemical Education, Inc.)PH detn. and acid-base titrns. are essential expts. performed by high school and university undergraduate students alike throughout their chem. education. While these expts. often rely on conventional pH meters for quantification and pH test strips or indicators for qual. assessments, we demonstrated herein that a smartphone-based pH detn. technique, performing digital image anal., particularly the detn. of either the dominant wavelength or the RGB intensities, could readily replace all but one conventional pH meter in a classroom setting. Using an inhouse developed smartphone-based pH reading application (app), students were able to det. the pH and perform titrns. using pH strips and universal indicators, producing results matching those detd. with a std. pH meter. The application and its "variants" are available for download (https://tinyurl.com/2dashjyk & https://tinyurl.com/4d73wnxt) and no prior knowledge of coding or programing was required from the students. All that was needed was an Android 11 phone or tablet with an Internet connection. Moreover, the students and instructors' reactions to the mobile app alike were very pos. and showcased the need and interest for such inexpensive technol., which allows for the running of an entire class for pH detn. of multiple real-life samples or acid/base titrn. without using std. pH meters.
- 14Sweet, C. Hidden or Invisible Disabilities and Laboratory Accommodations. In Accessibility in the Laboratory; ACS Symposium Series; American Chemical Society, 2018; Vol. 1272, pp 69– 75. DOI: 10.1021/bk-2018-1272.ch005There is no corresponding record for this reference.
- 15British Journal of Nursing - Colour vision deficiency: the ‘unseen’ disability. British Journal of Nursing. https://www.britishjournalofnursing.com/content/clinical/colour-vision-deficiency-the-unseen-disability/ (accessed Aug 2023).There is no corresponding record for this reference.
- 16Chromatic Vision Simulator > Home. https://asada.website/cvsimulator/e/ (accessed Apr 2023).There is no corresponding record for this reference.
- 17Online Catalogue. ACP Chemicals Inc.. https://www.acpchem.com/e/catalogue-public.asp?qNewOffset=301&qCategoryCode=16 (accessed Apr 2023).There is no corresponding record for this reference.
- 18Thermal Scientific. https://www.thermalscientific.com/product/3211/suppliers/emd-millipore-corporation/colorphast-ph-strips-emd-millipore (accessed Apr 2023).There is no corresponding record for this reference.
- 19The UDL Guidelines. UDL. https://udlguidelines.cast.org/ (accessed Aug 2023).There is no corresponding record for this reference.
- 20Meeks, L. M.; Jain, N. R.; Herzer, K. R. Universal Design: Supporting Students With Color Vision Deficiency (CVD) in Medical Education. Journal of Postsecondary Education and Disability 2016, 29 (3), 303– 309There is no corresponding record for this reference.
- 21Communicating data with colour. Victorian Government Department of Planning and Community Development. https://www.planning.vic.gov.au/guides-and-resources/guides/all-guides/communicating-data-with-colour (accessed Aug 2023).There is no corresponding record for this reference.
- 22Scanlon, E.; Legron-Rodriguez, T.; Schreffler, J.; Ibadlit, E.; Vasquez, E.; Chini, J. J. Postsecondary Chemistry Curricula and Universal Design for Learning: Planning for Variations in Learners’ Abilities, Needs, and Interests. Chem. Educ. Res. Pract. 2018, 19 (4), 1216– 1239, DOI: 10.1039/C8RP00095FThere is no corresponding record for this reference.
- 23Prieto, L. R.; Siegel, Z. D.; Kaiser, D. J. One Fish, Two Fish; Red Fish (or Green Fish?): Assisting Students With Color Vision Deficiency. Teaching of Psychology 2021, 48 (1), 90– 94, DOI: 10.1177/0098628320959946There is no corresponding record for this reference.
- 24Color and Universal Design. UXmatters. https://www.uxmatters.com/mt/archives/2021/09/color-and-universal-design.php (accessed Aug 2023).There is no corresponding record for this reference.
- 25Color Universal Design Handbook. Color Universal Design Organization, Tokyo . 2006. https://webcube-general.s3.amazonaws.com/eizo/media/contentassets/2015/10/09/handbook.pdf (accessed Aug 2023).There is no corresponding record for this reference.
- 26Why Do Colors Look Different on Computer Monitors & Screens? Quality Logo Products. https://www.qualitylogoproducts.com/promo-university/why-monitors-display-different-colors.htm (accessed Apr 2023).There is no corresponding record for this reference.
- 27Why don’t colors look the same across different devices? BenQ. https://www.benq.com/en-us/knowledge-center/knowledge/why-dont-colors-look-the-same-across-different-devices.html (accessed Apr 2023).There is no corresponding record for this reference.
- 28WebAIM: Contrast Checker. https://webaim.org/resources/contrastchecker/ (accessed Apr 2023).There is no corresponding record for this reference.
- 29Colour Contrast Analyzer. TPGi. https://www.tpgi.com/color-contrast-checker/ (accessed Aug 2023).There is no corresponding record for this reference.
- 30Coblis ─ Color Blindness Simulator. Colblindor. https://www.color-blindness.com/coblis-color-blindness-simulator/ (accessed Apr 2023).There is no corresponding record for this reference.
- 31Color Oracle. https://colororacle.org/ (accessed Aug 2023).There is no corresponding record for this reference.
- 32Nichols, D. Coloring for Colorblindness. http://www.davidmathlogic.com/colorblind/ (accessed Apr 2023).There is no corresponding record for this reference.