Accessibility refers to the ability of people with disabilities to have access to and benefit from an entity or system. Digital Accessibility refers to the ability of users with disabilities to effectively utilize information technology (IT) systems including web sites, mobile or web based applications, software and hardware. Digital Accessibility is generally concerned with ensuring that IT systems are designed in such a way that they interact appropriately with assistive technologies.
Extensive accessibility legislation is present in most of the major domestic markets including the United States, Canada, the European Union, Australia and Japan. Generally, the relevant portions of accessibility legislation require that organizations make best efforts in order to ensure that physical and electronic business areas can be used by individuals with disabilities.
As of the 2010 U.S. Census, 56.6 million Americans had a disability – roughly one in five individuals. Over 16% of the U.S. population between 21 and 64 and 49.8% of the population 65 and older is disabled. Americans with disabilities fall into several categories. 19.8 million Americans aged 15 years and older have a physical disability involving a limitation to mobility. 14.9 million Americans aged 15 or older have a sensory disability involving sight or hearing. The number of blind Americans is expected to grow from the current 3.3 million, to 5.5 million in 2020, according to studies conducted by the National Eye Institute. In tandem, the percentage of people with relevant disabilities using home computers, the Internet and related technologies will grow significantly during this time.
According to the 2001 Census and Participation and Activity Limitation Survey, 3.6 million Canadians experienced some form of disability that limited their activities. This represents a disability rate of 12%, generally on par with the disability rates of other first world nations. The disability rate increases with age – while 3% of the population aged 0 to 14 have a disability – 53% of the population aged 75 or over have a disability. The majority of this population, 2.4 million individuals, has some form of mobility disability. 950,000 individuals in the population have sensory disabilities including hearing or visual impairments.
In the 2009 Australian Bureau of Statistics Survey of Disability, Aging and Careers, one in five people in Australia (3.95 million) had a reported disability. This rate was much the same for males (19.8%) and females (20.1%). Of those with a reported disability, 3.39 million were limited in the core activities of self-care, mobility or communication, or restricted in schooling or employment. Most people with a disability were limited in one or more of these core activities.
Demographic trends throughout first world countries indicate that the citizens with disabilities, as part of the overall population, will grow over the next fifty years. This is generally interpreted as a sign that current disability legislation will be expanded or more aggressively enforced in the future.
A disability is concerned with an impairment of some fashion that impacts normal functioning. For the purposes of digital accessibility, three broad areas of disabilities are worthy of note: Sensory disabilities relating to an impairment of one of the five senses, mobility disabilities relating to some impairment of movement or coordination of movement, and cognitive disabilities relating to learning disabilities or impairment of the cognitive process.
The most common sensory disabilities are visual disabilities, ranging from mild visual impairments to total blindness, and auditory disabilities, including being hard-of-hearing or totally deaf. Sensory disabilities can be either congenital, due to an accident, or due to a disease. Given the visual nature of the web and most IT systems, individuals with visual disabilities are often those that are most acutely impacted by inaccessible IT systems. For example, consider a web site that contains charts and graphs representing a complex finding. A blind individual cannot perceive the visual chart image and without an accompanying text description would be unable to access the information in the chart.
Mobility disabilities involve impairment to some axis of motion, lack of fine motor control, or inability to perform synchronous actions. Individuals with paraplegia, quadriplegia or a temporary mobility disability, such as a broken bone in a cast, all demonstrate some form of mobility disability. Accessibility standards that impact individuals with mobility disabilities relate to control placement and keyboard usage. For example, consider a software application that requires the user to press “CTRL” and “C” at the same time as the only means of accessing the “Copy” function. A user with quadriplegia may have a difficult time activating this control chord given the requirement for fine motor control. To provide an accessible alternative, the copy functionality could be added to the main menu structure or right click context menu (or both) for the program.
Cognitive disabilities are a broad category and relate to some form of impaired cognitive functioning. One of the most common cognitive disabilities impacted by digital accessibility is dyslexia. Studies have shown that certain color palettes on web sites, and combinations of foreground and background colors, can be read more easily by individuals with dyslexia, than other color palettes.
Most people with severe disabilities use assistive technology in conjunction with core operating system functions to access information in digital systems. Assistive technology commonly refers to products, devices or equipment, whether acquired commercially, modified or customized, that are used to maintain, increase or improve the functional capabilities of individuals with disabilities. Assistive technologies that are commonly used by people with disabilities to interact with digital systems include:
- Screen readers, primarily used by people who are blind, which translate the text of electronic documents into speech.
- Braille keypads, primarily used by people who are blind, which render the text of web pages in a refreshable Braille display.
- Screen magnification software, primarily used by people with low visual acuity (low vision), enlarges selected components of the computer screen.
- Voice-recognition software, primarily used by people with mobility disabilities, translates speech into text and allows for control of a web browser utilizing only voice commands.
- Head pointers, primarily used by people with mobility disabilities, take the place of the mouse and allow individuals without fine motor control to move a mouse pointer around the screen.