Below you will find a list of some key principles of accessible
design. Most accessibility principles can be implemented very easily and
will not impact the overall "look and feel" of your web site.
- Provide appropriate alternative text
- Alternative text provides a textual alternative to non-text
content in web pages. It is especially helpful for people who are blind
and rely on a screen reader to have the content of the website read to
them.
- Provide appropriate document structure
- Headings, lists, and other structural elements provide meaning and structure to web pages. They can also facilitate keyboard navigation within the page.
- Provide headers for data tables
- Tables are used online for layout and to organize data. Tables
that are used to organize tabular data should have appropriate table
headers (the
> element). Data cells should be associated with their appropriate headers, making it easier for screen reader users to navigate and understand the data table.
- Ensure users can complete and submit all forms
- Ensure that every form element (text field, checkbox, dropdown
list, etc.) has a label and make sure that label is associated to the
correct form element using the
element. Also make sure the user can submit the form and recover from any errors, such as the failure to fill in all required fields.
- Ensure links make sense out of context
- Every link should make sense if the link text is read by itself.
Screen reader users may choose to read only the links on a web page.
Certain phrases like "click here" and "more" must be avoided.
- Caption and/or provide transcripts for media
- Videos and live audio must have captions and a transcript. With archived audio, a transcription may be sufficient.
- Ensure accessibility of non-HTML content, including PDF files, Microsoft Word documents, PowerPoint presentations and Adobe Flash content.
- In addition to all of the other principles listed here, PDF
documents and other non-HTML content must be as accessible as possible.
If you cannot make it accessible, consider using HTML instead or, at the
very least, provide an accessible alternative. PDF documents should
also include a series of tags to make it more accessible. A tagged PDF
file looks the same, but it is almost always more accessible to a person
using a screen reader.
- Allow users to skip repetitive elements on the page
- You should provide a method that allows users to skip navigation
or other elements that repeat on every page. This is usually
accomplished by providing a "Skip to Main Content," or "Skip Navigation"
link at the top of the page which jumps to the main content of the
page.
- Do not rely on color alone to convey meaning
- The use of color can enhance comprehension, but do not use color
alone to convey information. That information may not be available to a
person who is colorblind and will be unavailable to screen reader users.
- Make sure content is clearly written and easy to read
- There are many ways to make your content easier to understand. Write clearly, use clear fonts, and use headings and lists appropriately.
- Make JavaScript accessible
- Ensure that JavaScript event handlers
are device independent (e.g., they do not require the use of a mouse)
and make sure that your page does not rely on JavaScript to function.
- Design to standards
- HTML compliant and accessible pages are more robust and provide better search engine optimization. Cascading Style Sheets (CSS) allow you to separate content from presentation. This provides more flexibility and accessibility of your content.