Navigation shortcuts

There is a short menu at the start of every page that allows you to jump directly to the most important parts of the page, including main content and navigation. Sighted people who use the keyboard to navigate will see these links appear on screen when using the Tab key to navigate through the page.

Access keys

The site can also be navigated back to Homepage (following the UK Government access keys standard):

1 = Homepage

To navigate with access keys follow these steps:

"Windows": Hold down the "Alt" key and the access key. In "Internet Explorer", this must be followed by the "Enter" key.

"Mac": Hold down the "Ctrl" key and the access key.

Semantic markup

All pages follow a logical document structure. Screen reader users can get around pages quickly by moving between headings. Navigation menus are marked up as lists. Cascading Style Sheets (CSS) are used to control layout and presentation.

Text size

You can change the text size of this website to your preference through your browser:

In "Internet Explorer", select "View", then "Text Size", and then your preferred size.

In "Firefox" select "View", then "Zoom", and then "Zoom In" or "Zoom Out", or "Ctrl"/"Cmd + Plus" or "Minus". (Enable the "Zoom Text Only" option on that menu if you have a small screen.)

In "Safari" select "View", then "Zoom In" or "Zoom Out", or "Ctrl"/"Cmd + Plus" or "Minus". (Enable the "Zoom Text Only" option on that menu if you have a small screen.)

In "Chrome" select "View", then "Zoom In" or "Zoom Out", or "Ctrl"/"Cmd + Plus" or "Minus".


All content images used in this site include descriptive alt text. Purely decorative images have empty alt text.


Forms have their labels explicitly associated with their controls.


All link text has been written to make sense out of context, or else have explanatory title attributes.


Dynamic HTML has been used sparingly, and designed according to the principle of graceful degradation. If JavaScript is unavailable, all website content will remain accessible.

As some screen readers execute JavaScript but cannot effectively describe dynamic page changes, we recommend that screen reader users disable JavaScript in their browser's settings in order to avoid confusion.

Standards compliance

We strive to comply with the W3C WAI's Web Content Accessibility Guidelines and aim for our pages to conform to a minimum of "WAI-A" compliance. Wherever possible, level AA and AAA requirements are also met. See ''Caveats'' below.

At the time of launch, all pages validated to XHTML 1.0 Transitional.

You can find more information on accessibility by clicking the web accessibility links below:

Disability Discrimination Act (UK)

Section 508 (US)

W3C Web Accessibility Initiative


We cannot guarantee the accessibility of external information linked to from this website.

When we link to content in formats with reduced accessibility, for example Adobe PDF, Microsoft Word or Powerpoint documents, we indicate it up-front. Please contact us if you have difficulty accessing any information we link to, and we'll do our best to help.

As we are continuously updating our website, exceptions to the above accessibility standards may sometimes inadvertently be introduced. Please let us know if you have difficulty accessing any of our content.

PDF accessibility

If you use a screen reader or have special accessibility requirements, we recommend that you use at least Adobe Reader version 7. Click here for more information.

Contact us

If you experience any difficulty accessing this website, please do not hesitate to contact us.

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