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ACCESSIBILITY

The University of Delaware is committed to making information on its web site available to as many people as possible, which includes building ADA-compliant web pages. The following requirements not only address ADA compliance, but also serve those with older machines and modem connections.

Required:

Use meaningful "alt" tags to provide alternative text descriptions for images, image maps, sound files, Java applets and Flash files. Alternate text should describe the purpose of the images. For design images (like "spacer.gif" graphics and images used as list bullets, use empty "alt" tags (alt=""). Complex images like graphs or charts should also include detailed descriptions (longdesc="description.html").
All information conveyed with color must be available without color from the context or markup. Provide enough contrast between text and background color so people who cannot distinguish colors or those who use black and white screens can read your information. Use light backgrounds with dark colored text--the greater the contrast, the more readable the page.
When using video or animation, synchronize equivalent alternatives (e.g., captions or auditory descriptions) with the presentation.
Use style sheets and proper markup:
- Include a document type declaration (DTD) at the beginning of your document so that browsers know how to handle your code. Most Web page design programs can put this in automatically. Current recommendation: the HTML 4.01 Transitional DTD: i.e.,
  <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
- Use header elements to convey document structure and use them according to specification. For example, in HTML, use H1 as the main heading, H2 as a subsection of H1, etc. Mark up lists and list items properly.
- If possible, use CSS (Cascading Style Sheets) styles to control layout and presentation. For example, use the CSS "font" property instead of the HTML "font" element to control font styles. This separates structure from presentation and enables people with accessibility devices to apply their own style sheets to pages or override the style sheet altogether. A page should be structured so that it can be understood without the style sheet.
When using frames, title each frame with text that helps people understand its purpose and navigation.
Create data tables that can be read in a linear fashion.
- Provide row and column headers.
- Associate table cells with the proper header using the ID tag.
Make information provided through applets or scripting languages (e.g., JavaScript pop-up menus) available when the applet or script is turned off or provide a text alternative.
If you use file formats that require plug-ins for links to key information, provide a link to an accessible plug-in or an HTML version of the page at the same level.
Use height and width tags for images to allow the page to compose while the image is loading and to lay out the web page for browsers.
If all else fails, create a text-only version of your web page to make it easier for everyone to access the information.