18 - Accessibility

Class: CSCE-331

Notes:

Types of Disabilities and Barriers

In order to understand why web accessibility is necessary, it is helpful to have a basic understanding of the range of disabilities and their related barriers with respect to the consumption of web content.

Not all people with disabilities encounter barriers on the Web, and those with different types of disabilities encounter different types of barriers. For instance, if a person is in a wheelchair they may encounter no barriers at all in web content. A person who is blind will experience different barriers than a person with limited vision. Different types of disabilities and some of their commonly associated barriers are described here.

Watch the following video to see how students with disabilities experience the Internet.

In this video, David Berman talks about types of disabilities and their associated barriers.

People Who Are Blind

People who are blind tend to face many barriers in web content, given the visual nature of the Web. They will often use a screen reader to access their computer or device and may use a refreshable Braille display to convert text to Braille.

Common barriers for this group include:

For a quick look at how a person who is blind might use a screen reader like JAWS to navigate the Web, watch the following video.

People with Low Vision

People with low vision are often able to see web content if it is magnified. They may use a screen magnification program to increase the size and contrast of the content to make it more visible. They are less likely to use a screen reader than a person who is blind, though in some cases they will. People with low vision may rely on the magnification or text customization features in their web browser, or they may install other magnification or text reading software.

Common barriers for this group include:

See the following video for a description of some of the common barriers for people with low vision.

People Who Are Deaf or Hard of Hearing

For most people who are deaf the greatest barrier on the Web is audio content that is presented without text-based alternatives. They encounter relatively few barriers on the Web otherwise. Those who are deaf and blind will face many more barriers, including those described for people who are blind. For those who communicate with American Sign Language (ASL) or other sign languages, such as langue des signes québécoise (LSQ), the written language of a website may produce barriers similar to those faced when reading in a second language.

Common barriers for this group include:

Mobility-related disabilities are quite varied. As mentioned earlier, one could be limited to a wheelchair for getting around and face no significant barriers in web content. Those who have limited use of their hands or who have fine motor impairments that limit their ability to target web content elements with a mouse pointer may not use a mouse at all. Instead, they might rely on a keyboard or perhaps their voice to control movement through web content along with switches to control mouse clicks.

Common barriers for this group include:

People with Some Types of Learning of Cognitive Disibilities

Learning and cognitive-related disabilities can be as varied as mobility-related disabilities, perhaps more so. These disabilities can range from a mild reading-related disability to very severe cognitive impairments that may result in a limited use of language and difficulty processing complex information. For most of the disabilities in this range, there are some common barriers and others that only affect those with more severe cognitive disabilities.

Common barriers for this group include:

More specific disability-related issues include:

Everyone

While we generally think of barriers in terms of access for people with disabilities, there are some barriers that impact all types of users, though these are often thought of in terms of usability. Usability and accessibility go hand-in-hand. Adding accessibility features improves usability for others. Many people, including those who do not consider themselves to have a specific disability (such as those over the age of 50), may find themselves experiencing typical age-related loss of sight, hearing, or cognitive ability. Those with varying levels of colour blindness may also fall into this group.

Some of these usability issues include:

To learn more about disabilities and associated barriers, read the following:

Suggested Reading: How People with Disabilities Use the Web

Why Learn About Accessible Web Development

Curb Cuts

Curb cuts are a great example of universal design. Originally, curb cuts were added to sidewalks to accommodate those in wheelchairs, so they could access the road from the sidewalk and vice versa. However, curb cuts are helpful for many people - not just those in wheelchairs - including a person pushing a baby stroller, a cyclist, or an elderly person using a walker. The addition of a smooth gradient ramp allows anyone, who may have difficulty stepping or who may be pushing something, to smoothly enter the sidewalk via a ramp, rather than having to climb a curb. Although curb cuts were initially designed to help those in wheelchairs, they have come to benefit many more people.

From a web accessibility perspective, most of the accessibility features you might add to a website will have that so-called "curb cut effect." For example, the text description one might include with an image to make the image's meaning accessible to a person who is blind also makes it possible for search engines to index the image and make it searchable. It allows a person on a slow Internet connection to turn images off and still get the same information. Or, it allows a person using a text-based browser (on a cell phone, for instance) to access the same information as those using a typical visual browser. Virtually every such feature that might be put in place in web content to accommodate people with disabilities will improve access and usability for everyone else.

Key Point: Think of accommodations to improve web accessibility for people with disabilities as "curb cuts." These accommodations will very likely improve usability for everyone.

The Business Case for Web Accessibility

Video: The Business Case for Accessibility

Karl Groves wrote an interesting series of articles in 2011 and 2012 that looked at the reality of business arguments for web accessibility. He points out that any argument needs to answer affirmatively at least one of the following questions:

  1. Will it make us money?
  2. Will it save us money?
  3. Will it reduce risk?

He outlines a range of potential arguments for accessibility:

What accessibility really boils down to is "quality of work," as Groves states. When approaching web accessibility, you may be better off not thinking so much in terms of reducing the risk of being sued or losing customers because your site takes too long to load. Rather, if the work that you do is quality work, then the website you present to your potential customers is a quality website.

The 7 Principles of Universal Design

  1. Equitable Use
  2. Flexibility in Use
  3. Simple and Intuitive
  4. Perceptible Information
  5. Tolerance for Error
  6. Low Physical Effort
  7. Size and Space for Approach and Use