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You are viewing this page with a web browser which doesn't support some of the features used in this web site. This is probably because it is an old or non-standard browser. We recommend using a current and standard web browser to ensure the best results when viewing this site.

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This site has been developed to provide a common browsing experience for as broad a range of users as possible. It has been designed to conform to the standards recommended by the World Wide Web Consortium (W3C), for reliability, consistency, portability and accessibility.

The accessibility features employed in this site are listed below.

Screen resolution

This web site is designed to be viewed on screens configured with a resultion of at least 1024 pixels wide by 768 pixels high. It should be dispay adequately at resolutions down to 800 pixels wide by 600 pixels high, but may be difficult to use at lower resolutions. Most recent web browsing devices support the above screen resolutions.

Text sizes

This site uses Cascading Style Sheets (CSS) to define scalable fonts throughout all pages. You can increase or decrease the size of all text elements in this site as follows:

Internet Explorer 5, 5.5 & 6 - View | Text Size | (select a size)

Internet Explorer 7, 8 & 9 - Press the [Alt] key to display the menu and then follow the instructions for Internet Explorer 5, 5.5 and 6.

Internet Explorer 9 - Internet Explorer 9 also supports a 'Zoom' facility, which can be accessed by clicking on the 'Tools' menu (the 'cog' icon in the top right hand corner of the Internet Explorer window) and then click on 'Zoom' | (select 'in', 'out', or a percentage size).

Mozilla / Firefox 1, 1.5 & 2 - View | Text Size | (select 'increase', 'decrease', or 'normal')

Firefox 3 - View | Zoom | (select 'in' or 'out')

Firefox 4, 5 & 6 - Press the [Alt] key to display the menu and then follow the instructions for Firefox 3.

Safari 3 - View | (select required size option)

Safari 4 & 5 - View | (select required zoom option)

Google Chrome - Tools menu (the spanner icon in the top right hand corner of the Google Chrome window) | Zoom

Site navigation

All main navigation menus are consistent throughout the site and use text links only, ensuring that text-based browsers and screen readers will interpret them correctly. The main site menu is located as close to the top of the page code as possible, without compromising the rich content structure; text-based browsers and screen readers can skip directly to the main content via a special link, positioned as the first item of each page body, above all other code. All links within this site have been given meaningful names, so they make sense when taken out of context. We also use the 'title' tag with all links, to provide an additional supporting description.

This site does not support access keys as these are known to conflict with the functionality of some accesibility enhanced web browsers (e.g. screen readers for sight impaired users).

Document structure

Heading tags are used in a logical hierarchy, making the structure of all document content clear and unambiguous.


This site is designed to allow pages to be printed directly from a browser and appear the same in print as they do on screen with a standard, current browser and default settings. Additional background colours, which are used on screen may not appear in print; these have been removed to improve printing clarity and reduce printer ink usage.

Image descriptions

All images in this site include descriptive text, contained in the HTML 'alt' tag.

Use of colour

This site uses strongly contrasting foreground and background colours to ensure readability by people with impaired sight and in browsers with limited, or customised colour palettes.

Coding practises

  • This site has been developed to the W3C XHTML 1.0 standard.
  • This site does not require Javascript. Javascript is only used to manage specific functions in a manner which conforms with W3C standards. Browsers which don't support Javascript, or have it disabled, still have access to all content, formatting and functionality within this site.
  • All presentation styles and page layout within this site are controlled through W3C compliant CSS (Cascading Style Sheets).
  • Tables are only used for presenting tabular information in this site; they are not used for layout purposes. Where tables are used, they employ W3C standards to ensure the data they contain can be interpreted correctly by screen readers etc.
  • This site does not use 'spacer' images (e.g. for positioning and / or layout purposes).

Browser support

This site has been tested on a wide range of browsers and platforms. It has been designed to retain its consistent navigation and display in a logical and understandable format in older or non-standard browsers, including those with no CSS support.