Who is Accessibility For?

I have spent a fair bit of time lately reviewing potential accessibility issues on the websites I help administer. When I’m working on accessibility issues on my websites, I often think of how the site would work for a blind or sight-impaired person using a screen reader. A screen reader is a bit of software that reads aloud the content of a web page, and allows the user to navigate through the content using their keyboard rather than a mouse.

But accessibility is not just for blind people, and a screen reader is only one of a vast array of assistive devices that users may bring to your website. Your users could be color blind, for example. Or maybe they have a physical disability like a missing arm. They may have a neurological disorder like Parkinson’s disease that limits their fine motor control. They may not be able to hear well, or have cognitive disabilities that affect the way they process information or react to on-screen lights or motion.

They may be using assistive technologies other than a screen reader. Voice recognition, for example, is an assistive technology. There is a wide variety of alternative input devices to help people browse web content, including head pointers, foot switches, sip and puff switches, and eye-tracking devices. There are screen magnifiers, braille displays, and other kinds of reading assistants.

Plus, some accessibility features will make your website more usable for people who may have an impairment but who aren’t using an assistive device. Accessibility is not just for those with permanent impairments, but for anyone who might be temporarily impaired because of injury, illness, or medical treatments. Or they might have situational impairments based on where they are or what other things they are doing at the time. Or they might have technological impairments, like a slow internet connection or an expensive data plan.

Here is a diagram prepared by Microsoft Inclusive Design that gives some examples of permanent, temporary, and situational impairments. A touch impairment may be from having one arm, but it could also be from a temporary injury or because you’re carrying something. Similarly sight impairments could be from blindness, a cataract, or simply being distracted. Hearing impairments could be deafness, an ear infection, or being in a noisy environment. Someone with a speech impairment may be non-verbal, but they could also just have laryngitis or a heavy accent.

Users might also have technological impairments, like having a poor internet connection or an expensive data plan. In those cases your users might not be loading all the content from your site, and so good accessibility features, like image alt-text, are going to be important to them as well.

The goal of accessibility guidelines is to make your website easy to use for the largest possible number of people. Users regardless of their permanent, temporary, situational, or technological impairments ought to be able to perceive your content, use the site, understand the information you’re giving them, and your site should serve the same or equivalent experiences on many different kinds of devices with different technological capabilities.