Accessibility features of this web site

The accessibility of this web site is being improved in stages. Here is a summary of the improvements made so far, and the work that still remains. (Some of these features improve the appearance of this web site if styles sheets are not being used).

Improvements so far

Conformance to HTML and CSS standards

Pages on this web site are being validated in 3 main ways. As problems are found, they are corrected where possible. This is ongoing, not complete.

The HTML is being developed to 4.01 Transitional standards, for rendering in standard mode. Each page has a DOCTYPE stating this. This page and many others conform to this standard.

Vital information is not conveyed by text styles and colours, although they continue to be used where they enhance things for sighted people. They are controlled by style sheets. All style sheets have been validated for conformance to CSS-1 and CSS-2 standards.

Pages are also being tested against the "Bobby" standards for accessibility. This is a very long task, and indeed may never be completed. An example is that every page identifies its language, to help page readers interpret the text correctly.

• At the moment, pages typically fail Bobby validation because they control the width of buttons using pixel values. It may be possible simply to control the width using styles instead, without harming anything else.
• Some pages fail because they separate links with just white space, and some "readers" don't indicate where one link ends and the next one begins. It is not clear what the solution to this is. A problem is that putting a deliberate separator between the links can not only look wrong, but can be equally irritating when it is spoken by the reader.

Improvements in table structure

Nearly all tables now use both HTML header cell features and style features.

Improvements to come

Further improvements in table handling

Some tables will have "summary" information added to them.

Use of "alt" text for images

Some images have "alt" text that can be spoken by readers. Most do not have substantial text, although in that case they have "null" or zero-length "alt" text to avoid redundant speech by page readers.

In future, more "alt" text will be added for cases where images are not adequately described by the surrounding text.