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We feel strongly that doing our best to make our site accessible to all users is the right thing to do. We have made an effort to ensure that our website is viewable by most browsers and is accessible to everyone.

Alternate Stylesheets

Several alternate style sheets are available for the pages in this site including one specifically intended for those with disabilities (see below). However, old browsers will see very plainly styled pages. Upgrading to a more modern standards-compliant browser is relatively painless and will improve your experience on the web.

You may want to view our site map (or outline) and our site conventions to help you to browse our site more productively.

Stylesheets that may be useful to those with disabilities

A fluid layout that is suitable for use on any screen size, from very large desktops to tablets and mobile phones.
Larger Type
Our default type is already fairly large in comparison to many sites, but this style scales all type up a bit more for easier viewing.
Screen Reader
A fluid layout without banner graphics that includes links to skip navigation. This layout is intended for those needing a more accessible page, especially for those using screen-reader software.

If you have difficulty changing styles or if you have accessibilty issues or other comments about our site, please let us know (use the 'comments' link at the bottom of this page).

Design Standards

  • We employ stylesheets (CSS) to separate content from presentation and alternate stylesheets (see above) that present more accessible pages. The "Screen Reader" style (see above) will eliminate unnecessary graphics and provide skip navigation links to make browsing through menus less time consuming and repetitive for those using screen readers. Pages will degrade gracefully for those browsers that don't meet modern web standards.
  • HTML tags will be used to convey semantic meaning and the page should validate to the Document Type Definition (DTD) specified in the header of the page.
  • Tables will only be used to present tabular information, and never used for purely visual formatting. They will include textual information displayed in a linear form across the table.
  • Our site will not rely on javascript for navigation. Some features of the site will employ javascript (to set user preferences in cookies for instance), but these features will not be necessary.
  • We will not rely on proprietary technology for navigation or other essential features. However, where appropriate, we may include media that requires proprietary plug-ins.
  • Graphic images will have an "alt" tag, and a short description that can be intuitively understood by the user. If a graphic image is used as a navigation element, it will contain a text description and an indication of the link target that is intuitively understood by the user.
  • Every graphic image that uses an image map will provide alternative text of the hyperlink or present the same links in a separate list.
  • Links will be descriptive, intuitive, and avoid the use of vague references such as "click," "here," "link," or "this."
  • Links to non-HTML resources like PDF files will have an indication of the file type and size.
  • The use of frames and iframes will generally be avoided, as they cannot be read easily by all screen readers, create navigation and bookmark problems, and are not supported by all browsers.

We are trying hard to adhere to these standards, but our site is large and has evolved over time, so older pages may not meet our current design standards. We are working to revise our older content. Technology and accessibility standards are evolving rapidly, so please let us know what we can do to make our site more accessible to you, or if a particular page causes problems. We welcome any positive feedback regarding the accessibility of our website as well.