Colour vision deficiency and its impact on digital solutions focussing on GIS
What role does colour play in your organisation’s digital solutions? Is it to distinguish between different health and safety risk areas? Outlining environmentally protected zones through augmented reality? Or used within power automate application to red, amber and green score project status? No matter which area of modern day engineering you work within, colour plays a pivotal role in communication in all our day-to-day work.
Thinking about your organisation, its use of colour and what impacts are of risk of occurring if someone is unable to distinguish a colour? As a quite stark example, one in 12 men and 1 in 200 women are at risk of not being able to see health and safety risk zones on a map or being unable to view environmental boundaries when looking at project design information.
These are all very real risk that can occur when colour blindness (also known as colour vision deficiency or CVD) isn’t consider in digital solutions accessibility strategies. It is predicted that three million people in Britain have CVD which is roughly 4.5% of the current population, broken down into 8% of men and 0.5% of women. When considering the construction industry is 87% men, there is a further potential risk.
Environmental data including special sites of scientific interest can be impacted by CVD.
It was in my previous role as a graduate GIS data technician that I first noticed my CVD impacting my GIS work. I had shared with my team that I struggled with CVD, specifically protanopia. It first became an issue when I was trying to create custom widget icons for a new web app having been given a list of colours to follow. It was not until I completed this task that I was informed that more than 50% of the listed colours were not present in the new icons I had created. My struggles led to the development of a new accessibility strategy.
The commonly used phrase ‘colour blind’ is no longer considered correct due to the misconceptions associated with the label. Struggling with CVD doesn’t mean you’re blind to any single colour, rather you are less sensitive to some specific colours or shades which may cause them to merge and blend more easily, leading to difficulty in distinguishing colours. Of CVD there are three different types – protanopia, deuteranopia and tritanopia. Of these, the most common is deuteranopia which affects the perception of red and green.
So why does CVD impact men more often than women? This is due to the gene that can cause CVD being part of the X chromosome. Men inherit one X chromosome, so if the CVD gene is present on this single chromosome, then they will most likely have CVD. As women inherit two X chromosomes, the CVD gene would have to be present on both to cause CVD, making this much more unlikely.
It is vital to understand and adapt working methods within the GIS, digital and engineering profession to make sure we improve accessibility for all. Visualisation is key within all geospatial solutions as we are constantly deciding how maps, data and outputs should look, alongside how to communicate messages to end users and stakeholders. This is where a new CVD strategy comes into play, to make sure data is clear, concise and communicated effectively for everyone.
I currently work for Skanska, a partner on the @one Alliance project. This project is made up of a number of companies which work collaboratively to deliver the £1.31bn investment programme for Anglian Water and from more than 1,200 employees, 400 work within the ArcOnline space, the primary GIS platform. With one in 12 men and one in 200 women having CVD, there are potentially some who work in a colour dependent environment, such as GIS. It is essential, therefore, to make sure the maps are high quality visually to aid teams in the delivery of 700-plus projects across the region.
To achieve this a project was launched to improve the accessibility of the current main mapping and all future mapping solutions used throughout the design phase of projects. It also acts as a one-stop-shop for data, where anyone can view environmental data including nature reserves and flood risk areas, pipeline and electricity cable utility data, or the most recent census data – integral for mapping data on ecological constraints or health and safety risks, both for internal project assessments, communication, and for representing data for external stakeholders.
As a underexplored area within the industry and to make sure that maps would be CVD compliant, a new internal process needed to be developed from scratch. Tools, such as ArcGIS Pro’s CVD simulator which emulates the impact of CVD, as well as ESRI and NHS documentation, browser addons, conversations with experts and research, were used to build the internal @one alliance CVD compliance strategy.
The original aim was to assess and convert all 150-plus feature layers that were currently in active use with these main mapping solutions. With limited resources available the starting point was having several conversations with ESRI around its CVD accessibility articles, which had been published a couple of years earlier, alongside education relating to its ‘colour vision simulator’ tool which became available in ArcPro 3.1+. This gave a starting point to develop a CVD strategy.
The next step was to upskill the internal GIS team based on research through ESRI, government web content accessibility guidelines, and the NHS, to ensure the team would be informed of the risks and benefits of the new process. A ‘CVD Compliancy: Layers’ flow chart was created to highlight the correct process for anyone within the team to assess the CVD compliance of a feature layer. It also included alternatives that could be considered, alongside what to do if a colour cannot be changed. This was essential as every organisation has features where colours cannot be changed and providing alternative solutions through symbology where possible. This includes outline variations, unique icons, among others. If a feature can be understood without requiring the use of colour, then this provides accessibility.
The custom new process has seen alterations of 15% of colours associated with layers – not just data but the geospatial web apps they sit within too. All possible data has been amended to ensure anyone with CVD can confidently complete visual analysis and assessments for any project across the operational region of 10,600 square miles.
Another unforeseen impact is that most data affected by CVD was environmental data, including special sites of scientific interest, protected sites and carbon risk areas. These use red and green, one of the more common challenges for users with CVD. This meant that when an error is made based on these non-CVD compliant layers, it is much more likely to impact environmental protection areas. The project meant not only improving digital solution accessibility for users but ensuring the natural and built environments continued to be protected.
Having realised that it wasn’t just features and data that needed to be CVD compliant, but also web apps, a second process was built into the CVD strategy to allow for the assessment of web application by utilising brand-new tools such as the ‘colour contrast analyser’. This enabled further alignment with government web content accessibility guidelines.
This project is just one example of work being done to improve accessibility within GIS and digital solutions. Moving forward, it is essential to make sure that this process is consistently followed and applied to all further data, widgets, tools and web applications produced or procured.
I hope that published articles and presentations similar to this will help you think about your own use of colour in your organisations and how it can be adapted to not only improve accessibility for your users, but also reduce risks for our natural and built environments. There are some easy solutions that GIS specialists can implement even without committing to a full accessibility strategy.
Beyond CVD, the geospatial and digital world is considering accessibility in terms of neurodiversity and the experiences of people with autism, ADHD and dyslexia.
One example would be adding ESRI’s ‘enhanced contrast’ basemaps to your organisation’s basemap list as an option for users who may struggle with CVD. As an alternative basemap it can reduce the risks on some key CVD impacted colours.
As mentioned earlier, there are also certain pockets of data that cannot be altered due to specifications and requirements that are always in place, for example geospatial health and safety data. For this it essential to consider new and unconventional ways to alter data not just in colour but in symbology.
Such actions need to be completed carefully to make sure improvements for the few are beneficial, while not impacting the many, allowing for everyone to benefit from new accessibility strategies.
Beyond CVD, the geospatial and digital world is considering accessibility in terms of neurodiversity and the experiences of people with autism, ADHD and dyslexia.
Tailoring topographic maps for the blind and visually impaired was also a key discussion point at the 2023 UK annual ESRI conference and it’s great to see that the industry is increasingly focussing on this area. These discussions highlight the important work and increase awareness of these issues for many professionals and organisations.
There is still far to go but sharing best practice within professional communities will help to make the use of geospatial data and digital solutions more accessible for all.