Web site accessibility

10 February 2006

A guide to the methods of ensuring that the content and structure of web sites is both comprehensible and navigable to people with a range of disabilities.

Making web sites accessible remains a low priority for many organisations. Yet legal requirements, which are being either ignored or misunderstood, can result in fines, lawsuits and bad publicity. And there are surprising benefits that go beyond simply complying with equal-opportunity laws.

The Internet might be the ultimate medium for conveying information and services, but it does not necessarily make a significant difference to the way able-bodied people live their lives. But the implications for the disabled are arguably deeper. The lifestyle of a disabled person could improve significantly by, for instance, being able to shop online.

Not all web sites are accessible to everyone, however, and possible problems are not always apparent to the web site owner. Often, that is because the problems faced by the disabled user stem from the way the page has been written rather than the content.

Resolving these problems can be expensive but, equally, may provide other business benefits. Re-coding the site for accessibility purposes can be a substantial task, for example, but it can make the site usable by a far wider range of devices than just PCs.

Web browsers on PDAs and mobile phones are quite similar in capabilities to those available in an assisted device for accessing the web, since they generally support only text and use URLs based in HTML. That means that a site designed for a mobile device, with a stripped-down web browser and a smaller display, is probably accessible to the disabled, and vice versa.

Rights and requirements

The Disability Discrimination Act 1995 says that a provider of information must not discriminate against a disabled person. Although almost a decade old, the scope of the act, at least implicitly, covers the design and function of a web site, says legal consultant Stephen Mason. While no web site owner has been prosecuted under the act, charities have cited it when urging organisations to adapt their sites.

A more recent piece of legislation, which covers educational web sites, is more explicit. Since September 2002, the Special Educational Needs and Disability Act has made it illegal for institutions of higher education to provide electronic content that is inaccessible to disabled students.

Under the 1995 act, the definition of a service provider is broad: "Any person or organisation that provides a service to members of the public, whether they do so for free or in return for a payment." Equally broad is the scope of the services, which the act says include "access to and use of means of communications" and "access to and use of information services".

If a complaint about a service provider ever reaches the courts, it will be up to the service provider to show that its action were justified. Organisations contravening the act face fines that could run into tens of thousands of pounds and arguing that it costs too much to make a web site accessible is unlikely to be a successful defence, believes Mason. He cites a code of practice published by the Disability Rights Commission in 2002: "Whilst the code provides guidance to what is reasonable, it is difficult to believe that poverty could be used as an excuse for not ensuring the second or third generation web site is designed for the use of disabled people," he says.

Customer loyalty

"Disabled users will stay very loyal to a site that is accessible, if only because they've gone through the pain of trying to find a site that works, which can take a long time."
Jason Taylor, strategic business director, Usablenet

"Users with disabilities generally get quite poorly treated on the web. If your web site doesn't treat them badly, that's the one they'll use. And people communicate: if a company discriminates against someone, 10 other people will hear about it; if it doesn't, 10 other people will hear about that, too."
Jakob Nielsen, principal, Nielsen Norman Group

"Given the trivial cost of adding tags and checking critical paths through a site, minimal compliance should be a no-brainer - especially if it avoids even a single lawsuit or bad publicity."
Harley Manning, analyst, Forrester Research

"It is not only a legal requirement and a social responsibility, but also those organisations that are failing to ensure accessibility are slamming the door in the face of a highly receptive online market."
Deri Jones, CEO, SciVisum

"If we can make the site more usable for people with assistive technology, we can make it more usable for everyone."
Robert Folk, manager of editorial and content operations, Compaq.com

Design bluprint

The World Wide Web Consortium (W3C), which sets technical standards and issues guidelines for the Internet, has drawn up a set of recommendations for web site designers looking to create accessible web sites. Called the Web Accessibility Initiative, it is available from the W3C web site.

The key points for designers to consider are:

Provide a text equivalent for every non-text element, including images, video, applets and plug-ins and audio.

Ensure that all information conveyed with colour is also available without colour.

Ensure that equivalents for dynamic content are updated whenever the dynamic content changes.

Avoid designs that create screen flicker.

Use the clearest and simplest language appropriate for a site's content.

Identify row and column headers in tables.

Ensure that pages are usable when scripts, applets, or other programmatic objects are turned off or not supported.

How software can help

There are a variety of technological tools available that can make web sites more widely accessible. One particularly powerful tool is the cascading style sheet (CSS), which can be used to change the way that information is displayed on different devices. That is important since different disabled groups use certain types of devices with particular browsers and readers. An added bonus with CSS is that, given that they only have to be downloaded once, they can help to reduce server load since the formatting that used to be embedded in every web page now only appears in the style sheet.

The developers of the major web page design tools have been working hard to incorporate CSS support into their products. "Two or three years ago, we realised there was a significant opportunity - and requirement - to support people with impairments," says Fiona Coughlan, the UK managing director of Macromedia. "If you look at the legislation coming into Europe and the UK, it is some of the most stringent possible in terms of deploying web sites to customers." With each successive release of Dreamweaver, Macromedia's flagship web design tool, cascading style sheets have been added.

Another software company developing accessibility functions is Usablenet. Its Lift Transcoder product dynamically rewrites web pages to make them accessible as they pass between the web server and the user. For example, colours or fonts are changed or removed that would be difficult for certain users to read. GoLive's authoring tool has a similar facility.

Content management systems, when used correctly, should also pass content into accessible web page templates.

Golden examples

A quick spell of Internet surfing could without doubt throw up dozens of cases of web sites that do not comply with accessibility guidelines. An informal survey by Infoconomy has produced a few examples of good-practice, as well as some potentially problematic ones. (That is not to say that the latter group necessarily contravene anti-discrimination rules, but that there is arguably some room for improvement.)

Good eggs

Bad eggs

www.charlesschwab.com

www.amazon.com

www.cahoot.co.uk

Things to avoid

Long or complex texts may be difficult to understand for deaf users whose first language is signing.

Smaller text might be hard to read by people with impaired eyesight.

Navigating through an array of links may prove difficult for the physically disabled, who can use one of dozens of different tools instead of a mouse and keyboard to control a computer.

Epileptics may have adverse reactions to web pages containing blinking graphics/text.

A blind user accessing a web site with a screen reader - a program that reads out the text on the screen - will have no idea what information a picture is trying to convey.

Classic mistakes

Most of the steps required to make a site accessible should not prove too difficult to an experienced web site designer. But there are some common errors, say experts, such as:

Images
Don't leave the description tags for images blank: they'll just be read out by screen readers as 'Image'.

Meaningful URL
Screen readers read out the URL of the page first, so try to avoid meaningless URLs.

Red text
Differentiating features only by colour is bad. Colour-blind users may not be able to spot the differences, and users with low vision may not be able to either, even with a screen magnifier. Moreover, screen readers and Braille displays cannot pick up on different colour schemes.

Information Age: News, analysis & insight for IT & business leaders