Just as it is wrong to exclude someone from a physical building because they are in a wheelchair (modern public buildings generally have wheelchair ramps or elevators), it is also not right to exclude someone from a website because they have a visual impairment. We are all different, but we are all human, and therefore have the same human rights. The United Nations Convention on the Rights of Persons with Disabilities says that access to information and communications technologies, including the web, is defined as a basic human right.

Accessibility is the right thing to do. Providing accessible sites is part of the law in some countries, which can open up some significant markets that otherwise would not be able to use your services or buy your products. People with Disabilities are just as diverse as people without disabilities, and so are their disabilities.

The key lesson here is to think beyond your own computer and how you use the web, and start learning about how others use it — you are not your users. The main types of disability to consider are explained below, along with any special tools they use to access web content (known as assistive technologies, or ATs).

Note: The World Health Organization’s Disability and health fact sheet states that “Over a billion people, about 15% of the world’s population, have some form of disability”, and “Between 110 million and 190 million adults have significant difficulties in functioning”.

Types of Disabilities

Visual

Visual disabilities can range from mild or moderate vision loss in one or both eyes to substantial or complete loss of vision in both eyes. Some people experience reduced or lack of sensitivity to certain colors or color blindness, as well as sensitivity to brightness.

These include:

• Color blindness – difficulty distinguishing between colors generally red and green, or yellow and blue, and sometimes the inability to perceive any color.
• Low vision – includes blurry vision, seeing only the middle of the visual field, seeing only the edges of the visual field, and clouded vision.
• Blindness – substantial loss of vision in both eyes.

Cognitive, learning, and neurological

Cognitive, learning, and neurological disabilities involve neurological disorders, as well as behavioral and mental health disorders. They impact how well people process and comprehend information.

These include:

• Attention deficit hyperactivity disorder (ADHD) – involves difficulty focusing on a single task, focusing for longer periods, or being easily distracted.
• Autism spectrum disorder (includes “autism,” “Asperger syndrome”) – involves impairments of social communication and the ability to interact.
• Mental health disabilities – Including anxiety, delirium, schizophrenia, mood disorders. Relating to web accessibility, these conditions may cause difficulty focusing, processing, and understanding information. The medications used frequently have side effects including blurred vision, hand tremors, and memory impairments.
• Memory impairments – involves limited short-term memory, missing long-term memory, or limited ability to recall language. Dementia is one among many different causes of memory impairments.
• Perceptual disabilities (also called “learning disabilities”) – involves difficulty processing sensory information such as auditory, tactile, visual. This includes impairments in reading (dyslexia),writing (dysgraphia), managing mathematic concepts (dyscalculia).
• Seizure disorders – includes different types of epilepsy and migraines, which may be in reaction to visual or audio stimulation.

Auditory

Auditory disabilities include mild to moderation hearing impairment in one or both ears. Even partial loss or difficulty can be problematic in regards to audio content.

These include:

• Hard of hearing – mild to moderate hearing impairment in at least one ear.
• Deafness – hearing impairment that is substantial and uncorrectable in both ears.

Physical

Physical or “motor” disabilities are weakness and limitations of muscular control. These include: involuntary movements including tremors, lack of coordination, paralysis, limitations of sensation, joint disorders such as arthritis, pain that impedes movement, and missing limbs.

These include:

• Amputation – missing digits, limbs, or other parts of the human body.
• Arthritis – inflammation and damage to the joints.
• Paralysis – loss of control over a limb or other part of the body.
• Repetitive stress injury – involves injuries that occur to the muscles, bones, joints due to repetitive motion.

Speech

Speech disabilities include the inability to produce speech that is recognizable by other people or software. For instance, the volume or clarity of speech could make recognition difficult.

These include:

• Muteness – the inability to speak due to a multitude of reasons like mental disorders, cognitive impairments, or the ability to learn to speak.
• Dysarthria – weakness or paralysis of the muscles required to speak, including lips, lungs, throat, and tongue.
• Stuttering – speaking with continued involuntary repetition of sounds, especially initial consonants.

Usability Best Practices

For products to be usable, usability best practices must be incorporated throughout the design phase. Before creating visual designs, designers should give considerable thought to a site’s organization, navigation, and content. When usability is introduced at the end of a design process — or worse, at the end of development — usability changes can be limited in their efficacy and costly to implement. Incorporating these best practices early can help create better products under budget.

For sure, accessibility for all isn’t something to take lightly. And neither is it something that can easily be discarded considering that over 1 billion people in the world have disabilities. We, as world’s citizens, all have a part to play in creating a safe and comfortable place for everybody.

Because that’s what accessibility for all aims at: improving everybody’s lives, starting with some of the most vulnerable populations. People with disabilities face a whole different world than the one “able” people live in.

But we share common points and situations where accessibility for all takes its full meaning and truly improves our lives whether we are shopping, commuting, using our phone, wandering in a museum or the streets…

Let’s see what accessibility can do for us all! And how we can design it to suit us! You’ll discover that some technologies we use every day come from accessible solutions!