Overcoming The Issues

WCAG guidelines recommend that four points need consideration when designing an accessible site: 'perceivable', 'operable', 'understandable' and 'robust'. (W3.org, 2008) By evaluating these alongside the four main disability types, most accessibility problems will be resolved. WebAIM.org states that “some content will always be too complex for certain audiences. This is unavoidable.” (WebAIM.org, n.d. b) It is accepted that web developers can only do so much to make content accessible and assist as many disabled users as possible.

Four main types of disability need to be acknowledged: visual, audio, motor and cognitive.

Visual

Users may suffer from visual conditions such as blindness, glaucoma, cataracts or colour blindness. Sufferers are unable to perceive visual information on screen. Assistive technologies, like screen and braille readers (Fig. 2), navigate through the content in a linear fashion and convert it into audible speech or braille. They can struggle if a website isn't constructed considerately. Designers should use headers to identify sections of information and structure data tables and text so it reads correctly. Screen readers use the keyboard to navigate the web, therefore web content must be able to be 'tabbed' through. Elements requiring use of a mouse will be inaccessible and images can't be interpreted by a reader without additional 'ALT' text description. Video content requires a written transcript. Colour blindness means the user may interpret colour differently, so designers cannot rely upon it to convey meaning.

Audio

While those with auditory disabilities don't have a problem with understanding text and images, there are issues with streaming video and audio content. It is necessary to provide a written transcript, audio captioning or subtitles. Often, the video quality makes sign language or lip reading impossible. There are also difficulties with the differences between international sign languages.

Motor

Those with decreased mobility often don't have fine enough motor control to use a keyboard or mouse nor 'click' on individual elements. Motor conditions include paralysis, cerebral palsy, Parkinson's disease, multiple sclerosis and arthritis. To compensate, designers must ensure all functions are available via the keyboard. A 'skip to' content function is beneficial as some assistive technologies can cause fatigue for users. These devices include mouth sticks and head wands which allow users to type and navigate using the keyboard, whereas sip-and-puff switches “interpret the user's breath actions as on/off signals.” (WebAIM.org, n.d. a.)

Cognitive

Cognitive conditions encompass many things, Disabledworld.com states “Persons with cognitive disabilities may have difficulty with various types of mental tasks.” (n.d.) They are unable to process multiple tasks and have issues with attention span, memory and comprehension of text and images. Conditions can include Down's syndrome, traumatic brain injury, dementia, dyslexia and dyscalculia. Developers can attempt to overcome these issues by ensuring complex tasks, such as purchasing goods are explained at the beginning and that any errors are made plain. The website should function predictably with no surprise elements, text content should be structured with headings, lists and kept to short, simple sentences.

Web accessibility is a fundamental principle of good web design. As long as coherent site is planned from the outset and semantic code is used, there should be no excuse for it's lack of implementation, even with established sites where the changes are more extensive. It allows everybody to enjoy and benefit from the web, regardless of ability.

Fig. 2 - Close Up of a Braille Reader

Fig. 2 - Close Up of a Braille Reader

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