The World Health Organisation has estimated that there are around 600 million people with disabilities worldwide.
Over 10 million of these are in the UK and they have a powerful spending punch of around £80bn. With this in mind, it's vital that your business website caters to this part of the population. If anything, it makes sound commercial sense to make sure that every visitor to your website is fully satisfied with the service and can access the content with no hassle.
If you make an effort to render your website 'accessible' then as well as helping people with disabilities, there are other welcome side effects.
Accessible websites have smaller file sizes so your website pages will load faster and in turn this will mean lower hosting costs.
Also, search engines can read accessible sites much easier - so your website will climb up within the search rankings.
Finally, and perhaps most importantly, the Disability Discrimination Act in the UK rules that there is a legal obligation in this country to have an accessible website.
The act "makes it unlawful for a service provider to discriminate against a disabled person by refusing to provide any service which it provides to members of the public."
It goes on to say: "For people with visual impairments, the range of auxiliary aids or services which it might be reasonable to provide to ensure that services are accessible might include [...] accessible websites. For people with hearing disabilities, the range of auxiliary aids or services which it might be reasonable to provide to ensure that services are accessible might include [...] accessible websites."
In order to meet the minimum standards of accessibility, there are certain functions websites need to have.
Firstly, they need to supply adequate text descriptions for any graphic content so that visually impaired people can 'read' pictures, and should supply equivalent alternatives to auditory and visual content.
Also, websites should not rely on colour to convey information as many people cannot differentiate between certain colours.
Style sheets should be used to manage the presentation of the website and must use proper structural elements.
These are just a few of the many standards that websites are supposed to reach in order to classify themselves as accessible.
The current guidelines recommend that websites use World Wide Web Consortium (W3C) technologies. W3C is a member organisation, founded by Tim Berners-Lee. It aims to raise the standard of the web and provides advice, guidance and help on increasing the accessibility of your site.
However, in a survey released in December 2006 by web accessibility agency Nomensa, it was revealed that 97% of websites do not achieve the minimum web accessibility level.
The firm tested 100 sites across 20 countries in sectors such as Heads of State, airlines, banks, newspapers and retailers. Only three sites met the criteria of Web Content Accessibility Guidelines (WCAG): the German Chancellor's website, the Spanish Government website and Tony Blair's site - all government websites.
"With online information linking people together it is vital that sections of the global population are not alienated and left out as innovation continues apace," says Simon Norris, managing director of Nomensa.
Many sites almost compliant
Yet, noted Norris, "while only three websites made it on to the first rung of the accessibility ladder, many websites were in grasping distance of achieving minimum levels of accessibility."
In order to make sure that your website doesn't fall short of the guidelines, consider following the five-step exercise recommended by the Royal National Institute for the Blind (RNIB) to see what improvements and changes you may have to make.
Research and get to know the standards, which not only cover accessibility, but design and usability too. IBM checklists are an ideal place to start.
Test your own website. The singularly most important standard is that your site is usable without a mouse - so try to carry out every task and action without one. If this standard was implemented on every single site then most users would have no barriers to accessing the net.
Look into using alternative interface colours. Some blind, partially sighted or dyslexic people experience glare from the screen and may work better with certain colours.
Sit with a user and see how they interact with your website. You will learn a lot from seeing how a blind user, for instance, carries out a task.