Digital Accessibility Testing and Validation
If you haven't already checked out the Digital Accessibility Basics Training Series, please do so when you have a chance! This series will provide some context for any of the accessibility evaluation tools listed below.
Digital Accessibility Checklists
How do you find the right accessibility checklist to use during the design process? Well, the World Wide Web Consortium does make a series of resources available to verify the accessibility of your digital content.
- W3C’s Web Content Accessibility Guidelines (WCAG) 2.0
- W3C’s How to Meet WCAG (Quick Reference)
- W3C’s Appendix B: Checklist (Non-Normative)
These checklists can be helpful to developers but may be overwhelming for content editors who have less experience with digital design. That being the case, Web Accessibility in Mind, or WebAIM, has developed a more digestible set of accessibility principles: Quick Reference: Web Accessibility Principles. They have also created a more user-friendly version of the WCAG 2 checklists: WCAG 2 Checklist.
Automated Accessibility Evaluation Tools
There are a significant number of free automated accessibility evaluation tools available online. Siteimprove is a quality assurance tool to which all pdx.edu content editors may request access. In addition to measuring quality assurance by catching things like misspellings and broken links, Siteimprove will also test for missing alt text or heading structure. Visit UCOMM's FAQ web page for details regarding Siteimprove Access. The following are some additional automated accessibility evaluation tools that may be helpful to you:
Note that automated accessibility evaluation tools will only help you to locate and repair the most obvious accessibility issues. To ensure WCAG 2.0 compliance, you must evaluate materials manually.
Manual Testing with Adaptive Technology
At minimum, digital content should be tested for navigation structure, keyboard accessibility, use of color, and media accessibility. Optimally, screen reading software can be used to determine whether all functions can be accessed equitably via keyboard. The following are some resources to help you get started:
- WebAIM: Testing with Screen Reading Software
- WebAIM: Using NVDA to Evaluate Web Accessibility
- WebAIM: Using VoiceOver to Evaluate Web Accessibility
Niklas Petersson, a native screen reader user from Miles Access Skills Training, created the following two, short videos illustrating the way someone who uses screen reading software might access images:
- Evaluating Content for Accessibility: Screenshots (Part 1) provides an example of a screenshot that has been incorporated in a webpage in a way that is accessible via screen reading software.
- Evaluating Content for Accessibility: Screenshots (Part 2) offers an example that is far less useful.
Color Contrast Evaluation Tools
In order to use a color contrast evaluation tool, you will need the hex or RGB key for the background and foreground colors you plan to use. If you are unable to determine this information easily within your content editing tool, you can use a tool like the Eye Dropper extension for Google Chrome.
Once you've determined the hex or RGB keys, you can use any of the following color contrast ratio checkers to evaluate contrast between background and foreground colors. WCAG 2.0 guidelines recommend at least a 4.5:1 contrast ratio. All of these color contrast checkers will indicate whether or not specific color combinations comply with WCAG 2.0 Levels A and AA, at or below size 18 font.