Location is everything – finding it is another. Being able to find places easily is key to getting out and about at any age or level of capability. Online maps are becoming more sophisticated with interactive content and different layers of information. Graphics and colour are used to emphasise places and attributes. But not everyone can see certain colours. So, does your access map have the right colours?
The number of people with colour vision deficiency (CVD) is growing as some people acquire it as they get older. Map Design for the Color Vision Deficient provides a background to this issue and tools for selecting the colours when designing maps. You will need institutional access for a free read. A similar paper is available on ResearchGate.
The golden rule of map design states that one should carefully consider both a map’s purpose and its audience. Maps designed for the general public frequently fail to consider the portion of our population with color vision impairment or color vision deficiency (CVD), known more commonly as color blindness. Recent studies indicate that over 5% of our Caucasian male population are susceptible to congenital or inherited color vision deficiency.
CVD also can be acquired from chemical exposure, injury, illness, medication, and aging. With the exception of aging, little or no data exists on the number of people impaired by any of these non-congenital causes. The predominant color impairment from congenital CVD is a red-green differentiation problem, whereas blue is considered universally recognizable by the congenital group. However, recent research has revealed that as many as 20% of those studied over the age of 72 suffer from a blue-yellow defect that increases with age to nearly 50% at age 90.
This acquired blue-yellow defect also is the predominant CVD for those suffering from chemical exposure. This chapter examines the effects of CVD and attempts to illustrate the impact of color choices on visually impaired audiences. It shows that the acquired CVD population is growing and suggests colors and alternatives in map design to minimize that impact. Finally, it introduces several tools that may be used in selecting appropriate colors or used to evaluate color choices when designing maps.