Mobility impairment is not always as obvious as one might think. You don’t have to imagine extremes of disability like paralysis or amputations. Try to imagine a simple fall or other accident that results in both hands being in a cast and being unable to use the mouse. Now, with that in mind, open up your website in your browser, put a blunt pencil in your mouth, and try using the eraser to press the TAB key until you get to the main content of your page. With a correctly placed “skipnav”, a TAB key click takes you to the link, and an ENTER key click takes you to the main content. That is accessibility. It’s the web equivalent of an on-ramp.
A skipnav is a link placed at the beginning of the page (before any other content on the page) that allows the user to skip all topbar and sidebar navigation links and go directly to the main content. This is usually a simple text link placed at the beginning of the header or in a separate DIV before the header. It is one of the few pieces of page content that is considered acceptable for cloaking (matching the text color to the background color or using CSS to resize it or slide it off screen so it is invisible to the user). . Like most accessibility options, it exists. primarily for disabled users and does not have to be visible to be useful.
Web design for limited mobility also includes checking your scripts to see if their behaviors are mouse-centric. Without touching the mouse, try to scroll through your site. There are no perfect keyboard equivalents for all mouse events, but the main ones are pretty basic. If you have a CLICK event, add the same KEYPRESS event. If you have a MOUSEOVER event, add the same FOCUS event. If you have a MOUSEOUT event, add the same BLUR event. Accessibility is about making the page useful to everyone, no matter how they get to it or have to navigate around it.
The anchor tag’s ACCESSKEY value is another nice and rarely used feature to add to your navigation system. Although it’s currently not supported by some browsers and browser versions, it’s one of those things that doesn’t hurt your page by being there. Browsers that don’t support it simply ignore it. Users hold down the ALT key (the CONTROL key for Mac users) and press the specified single alphanumeric character to set focus or activate a link depending on the browser. Allows you to set keyboard shortcuts for main site navigation.
Other aspects of mobility impairment related to computer use may not initially occur to you. These include slow reflexes, lack of coordination, tremors, ticks, paralysis, arthritis, and anything else that might make a user’s hands uncooperative. I for one am having a hard time double-clicking fast enough (due to nerve damage) for the computer to register it as such. So avoid page layout that relies on site visitor speed and eye/hand coordination, unless of course you want your page to feel like a video game. Avoid single character or single digit hyperlinks on a page or image maps with small hot spots. (I know, scripted imagemaps are another problem.)
You wouldn’t believe the number of web pages I’ve been to that use words like “I” or the number “1” as links to important content. Try to reach that after six cups of coffee. Our goal is not to make it difficult for site visitors to use our sites; it’s about making it easier and more intuitive. That is usability. It’s the web equivalent of a well-ordered office directory, neatly posted on the wall with neatly labeled signs on each door.
I know these things will take a little more time and effort, but they are worth it. It’s just not that hard to imagine yourself in need of them.