What is accessibility?
Accessibility is the practice of making a website usable by as many people as possible. This often means providing more than one way to access information or complete a task on the website. People with disabilities may not be able to read, hear, or click a mouse. This may be a permanent disability, or a temporary disability caused by injury or environment.
Similar to making accommodations for changes in technology like mobile phones or tablets, making websites accessible for people with disabilities should be considered equally essential.
Another way to think of accessibility is providing everyone with an equal opportunity to use your website no matter what their ability.
Why should a website be accessible?
Just as it is wrong to exclude someone from a physical building because they are in a wheelchair, it is also wrong to exclude someone from a website because they have a physical impairment.
Beyond the human concept of the right thing to do, it is the law in many places. Many lawsuits have been filed and won against businesses with websites that are not accessible. In the U.S., the American with Disabilities Act requires businesses to comply with web accessibility standards.
According to the Center for Disease Control, 61 million adults in the U.S. (1 in 4 adults) report having some form of disability. Accessibility ensures that all potential users, including those with disabilities, can access website information. This, in turn, can increase the customer base and market share.
Improving accessibility for people with disabilities has the added benefit of improving the experience for people using the website in less-than-ideal conditions. Some examples may be using a mobile device, being in low light, having a slow network connection, being in a loud or distracting environment, glare on a screen, etc. Implementing accessibility best practices also improves the usability of the site for all users.
Types of disabilities
Making a website accessible includes considering several different types of disabilities (both permanent and temporary) that may impair someone’s ability to use the site. Many people think of accessibility as adding options to a website for blind or deaf people. In fact, there are a wide variety of disabilities that affect individuals, and each requires its own assistance.
Below are categories of types of disabilities.
- Physical or Motor Skill disabilities – Limitations of muscular control such as tremors, paralysis, involuntary movement, or missing limbs. This may limit the ability to use a mouse or keyboard. Permanent examples are amputation, arthritis, and paralysis from a stroke. Temporary examples are repetitive stress injury, a broken finger, or an arm in a cast or sling.
- Visual disabilities – Limitations on sight such as blindness, low vision, or color blindness. This may limit the ability to read or see a video. Permanent examples are blindness, color blindness, or macular degeneration. Temporary examples may be forgotten glasses, eye injury, or low-light conditions in the environment.
- Hearing disabilities – Limitations of hearing such as complete or partial deafness, or an inability to hear certain frequencies. This may limit being able to hear alerts or audio content. Permanent examples are total deafness, or partial loss from a medical issue or injury. Temporary examples are an injury, bandaged ears, or noisy conditions in the environment.
- Cognitive/Neurological disabilities – Limitations in processing data. These users may have difficulty remembering information, may be easily distracted, and may have learning disabilities that affect how well they read text. Permanent examples are ADHD, Dyslexia, or an anxiety disorder. Temporary examples are emotions, task related stress/anxiety, or distractions in the environment.
- Seizures – Some users may be prone to photo-epileptic seizures, so that flashing, strobing, and blinking graphics are a danger.
Accessibility should be part of design and development of a website from the beginning. It is more difficult and costly to address accessibility after the fact. Below are some guidelines for how to approach making a website accessible.
The W3C WCAG (Web Content Accessibility Guidelines) POUR principles create the functional accessibility necessary for people with visual, auditory, mobility, and cognitive disabilities to access website content, and applies to all platforms.
The principles to be followed are:
- Perceivable – Information and user interface components must be presentable to users in ways they can perceive. It can’t be invisible to all their senses. (Example: For a blind person, a screen reader should be able to perceive a button.)
- Operable – User interface components and navigation must be operable. The interface cannot require an interaction that a user cannot perform. (Example: For a person who can’t use a mouse, there should be a way to perform actions using the keyboard.)
- Understandable – The information and the operation of the user interface must be understandable. The content or how to perform the operation cannot be beyond their understanding. (Example: Using clear and simple text to explain required actions.)
- Robust – Content must be robust enough that it can be interpreted reliably by a wide variety of user agents, including assistive technologies. As technologies and user agents evolve, the content should remain accessible. (Example: new accessible keyboards for paralyzed users.)
Some good guidelines to consider for making accessible digital content are below.
For Physical impairments:
- Provide information in multiple formats. For example:
Provide visual access to audio content (captions, transcripts).
Provide transcripts for audio content.
- For mouse actions, also provide a keyboard-only solution.
- Provide strong color contrast and sufficient font size for content.
- Do not rely on color alone as a navigational tool or to differentiate items.
- Functionality should be accessible through mouse and keyboard and tagged to worked with voice-control systems.
- Images should include Alt Text in the markup/code, and complex images should have more extensive descriptions (possibly captions or a summary in an accompanying paragraph).
- Sites should have a Skip Navigation feature for screen readers.
- Consider 508 testing to assure your site is complying (Section 508, Rehabilitation Act of 1973).
For Cognitive impairments:
- Deliver content in more than one way, such as by text-to-speech or by video.
- Provide easily understood content, such as text written using plain-language standard.
- Focus attention on important content (possibly with headings or placement).
- Minimizing distractions, such as unnecessary content or advertisements.
- Maintain consistent webpage layout and navigation across the website.
- Use familiar web elements for easy recognition, such as underlined links in blue.
- Divide processes into logical, essential steps with progress indicators.
- Make website login/authentication as easy as possible without compromising security.
- Make forms easy to complete, with clear error messages and simple error recovery.
Sources / Related Reading
What is accessibility? - Learn web development | MDN (mozilla.org)
Types of disabilities: Understanding accessibility: Accessibility: Indiana University (iu.edu)
Accessibility Basics | Usability.gov
Accessibility Principles | Web Accessibility Initiative (WAI) | W3C
Types of Disabilities | Usability & Web Accessibility (yale.edu)
Web Accessibility Laws in the U.S. (rev.com)
Home | 18F Accessibility Guide
Beyond Accessibility: Treating Users with Disabilities as People (nngroup.com)
Accessibility Standards - Santa Barbara City College (sbcc.edu)
3 Great Reasons to Make Your Website Accessible - SitePoint
Accessible Websites Are Better for Everyone (And Better For Business Too) (forbes.com)