A brief introduction to DDA Compliance

Considering making your website DDA compliant? Here's a quick introduction to the key considerations effecting marketeers and website managers.

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Our clients, particularly when starting new projects often ask us about DDA compliance.

So, what are the minimum requirements and ongoing commitments to achieve and self certify a AA rating for your website?


Consider the visitor to your website

For those unfamiliar with accessibility issues pertaining to Web page design, consider that many users may be operating in contexts very different from your own:

•    They may not be able to see, hear, move, or may not be able to process some types of information easily or at all.
•    They may have difficulty reading or comprehending text.
•    They may not have or be able to use a keyboard or mouse.
•    They may have a text-only screen, a small screen, or a slow Internet connection.
•    They may not speak or understand fluently the language in which the document is written.
•    They may be in a situation where their eyes, ears, or hands are busy or interfered with (e.g., driving to work, working in a loud environment, etc.).
•    They may have an early version of a browser, a different browser entirely, a voice browser, or a different operating system.

This document aims to provide useful impartial guidance on the application of the W3C Accessibility Initiative which summarises DDA compliance for your website development and content.


Your website architecture and content for DDA compliance

Here are some helpful pointers that have been taken from the W3C Accessibility Initiative that you can use as a quick reference guide to understand the implications of seeking AA level compliance. These and can also be viewed at: http://www.w3.org/WAI/WCAG20/quickref


• All text should be of a suitable contrast to their background – for AA a ratio of 3:1
• All text where possible should be resizable without the use of particular technology (the web browser)
• All text should be used without any graphic images and as system fonts, except where it is essential for the brand (for example the logo)
• The site should be written in plain, simple English

Images, Video and animations

• No use of Flash
• All images to have alt tag information
• There should be no uninitiated movement – therefore any animations must be started by the user
• All videos should have suitable captions and provide all spoken words in written format as an alternative. Where possible this includes a narrative of the video visual content


• The site should be able to be navigated with simple keyboard/spoken commands (therefore we cannot apply critical effects or functionality on hover/rollover), this also effects the use of content applied in the lightbox style container (screen darkens and content appears in new window)
• The website should not open any new windows, without explicit direction, therefore external links should open in the same window, again this applies to lightbox style content
• Colour should not be used to distinguish navigation or content (effectively the website should be fully useable in greyscale/monochrome
• The site must be fully useable with JavaScript disabled


• All pages to have a Meta description to summarise the page content
• The site will be built adhering to all technical requirements, such as style sheets (CSS), validating HTML at time of handover/project completion etc
• The site should not require any horizontal scrolling, unless alternatives have been provided. Meaning in it could be argued a fluid layout is required to work at all resolutions, see: http://www.adur.gov.uk as an example of a fluid layout, where the content resizes etc to fit the browser window.


Auditing your site

The 3WC and all other DDA guidelines are self-policed. There is no official governing body and the status of the website is generally assessed by the web-master managing the site in question. The guidelines are a set of best practice guidelines and advice on how to design, configure, build and maintain your website to be useable by all. Here are a few methods of how you could approach this:

Online testing

The online testing website which exist are not considered to be suitable to audit a website for it’s DDA compliance. As the guidelines are open to interpretation a human being is required to scrutinise the website and it’s content, this cannot be automated.

For example, the website Adur District Council which is very focussed on DDA compliance: http://www.adur.gov.uk/accessibility/accreditation.htm. This site does not validate on the tool at either of these tools: http://validator.w3.org/ (HTML validation only) or http://www.dda-compliant.com/testing/ these tools offer no guidance as to how to fix any errors or failings.

Third party auditor agreements

As third party audits may vary due to the possibility of differing interpretations of the guidelines it is advised that if a third party auditing company is to be involved that they are involved from the beginning to ensure the website is built to a pre-agreed set of guidelines.

Self-certification of the website

The last option is that you yourselves or your project team decide whether the website is optimised to a certain acceptable level – in accordance with the 3WC Accessibility Initiative and as such self certify your website as AA or AAA.

In conclusion, when building and designing a DDA AA compliant website based on this information you will need to decide if the limitations of the DDA guidelines will impose on certain functionalities of your site.


Text only and hi-visibility alternatives – an excellent compromise

It is also a consideration that the W3C guidelines consistently refer to the fact of having ‘a suitable alternative made available’. As detailed above the text only with resizing and hi-visibility options will provide a suitable alternative for all users of the website. This is the most common way of providing a truly accessible website without the need to compromise on front-end development techniques or the effectiveness of the website content for the vast majority of visitors.

An example of this can be viewed on the Somerset College website - click here to see this text only version (click 'Text only' on the top left of the home page).

By creating a text only alternative and ensuring that as much of the initiative is adhered to as possible throughout the main website we believe it is possible to create an acceptable site for all. This includes readable text, suitable image alternatives, ease of navigation etc.



DDA compliance is an important consideration, often essential for those working in the public sector. Ultimately it is a commitment by your organisation to support the users of your website who may not be able to browse the web as you can. This will mean compromises on some functionality and additional work to ensure all content is published in the correct way.

By providing at least some basic tools to enable anyone to use your site, such as a text only version, you may incur a little extra cost but ultimately will create a good impression to all users and you may even pick up extra business as a result of your website being accessible to all.

Melon is able to provide website design and development to any level from A to AAA, please feel free to contact us to discuss a website project or leave a comment below.