NVDA Basics for Web Accessibility Testers
- Pamela Thomas
This guide is intended for Syracuse University staff who would like to use NVDA as part of a WCAG 2.x assessment of a web site or web application. It is not intended to be a comprehensive introduction to the NVDA screen reader. For in-depth instruction on using NVDA please refer to the training materials on the NV Access Get Help page.
The WCAG 2.x A and AA Manual Evaluation form used by Syracuse University staff for testing web sites and web applications includes a number of checkpoints that are best tested using a screen reader. The following table lists the relevant checkpoints, a recommended testing technique with the corresponding NVDA keystrokes, and video clips illustrating NVDA output for each command.
Remember, if you want NVDA to stop talking, just hit your CTRL key!
Once running, all settings, help, commands, and functions are available by clicking the NVDA icon in the system tray.
Getting Started Tips:
- NVDA is designed for use in Firefox and may not work well with other browsers.
- When you start NVDA it will start with mouse tracking enabled, this means that if you move your mouse it will interrupt what is being read and move the focus to your mouse. You may want to turn this off because you will be using your mouse to scroll the screen view during testing. To toggle mouse tracking on/off, use Ins + M.
- To speed up or slow down NVDA reading speed, click the NVDA icon in your Windows notification area and choose Preferences > Settings > Speech.
- To turn NVDA off or modify settings, click the NVDA icon in the system tray.
| Step | WCAG Checkpoint | Description | NVDA Keystrokes | Video |
|---|---|---|---|---|
Listen to the Page (Note: NVDA does not automatically scroll the view while reading) | 2.4.2 2.1.1 | Check that the page title is descriptive. Listen for content that might be missed by NVDA. Check that the content reading order is logical and intuitive. Listen for alternative text on images. Check that navigation regions and main content regions are announced. | Ins + Down Arrow CTRL (Stop talking) | |
| Tab through the interactive elements on the page | 2.4.1 1.3.2 | Confirm that there is a Skip Navigation option and that it is functioning properly. Confirm that navigation menus function and that menu options are announced properly. Confirm that tab order is logical and intuitive. | Tab (Move forward) Shift + Tab (Move back) Spacebar (Activate a menu) Up arrow/Down Arrow (Move through menu items) Esc (Close popup windows) | |
| Check for headings | 1.3.1 2.4.6 Headings are used and nested appropriately | Use the Headings List dialog box to check for the presence of headings and that heading structure is logical and begins with Level 1. | Ins + F7 (Choose Headings) | |
| Check for descriptive links | 2.4.4 Link text is descriptive | Use the Links List dialog box to check that all links make sense out of context. | Ins + F7 (Choose Links) Use the 'Move to' button to locate a suspicious link on the page. | |
| Check for alternative text | 1.1.1 Alternative text on images, buttons, embedded multimedia, and frames is appropriate and meaningful. | Check the alternative text on images and other graphical elements. | G (Read next graphic) Shift + G (Read previous graphic) or Ins + M (To turn on mouse tracking) Mouse hover to read alternative text | |
| Verify that forms are properly labelled and that all fields are usable. | 3.3.1 | Use the Form Fields dialog box to check that all form fields, including search fields, are properly identified and include informative labels, the type of form element (text field, checkbox, radio button, etc.) as well as the current state of the element (checked, not checked, etc.) | Ins + F7 (Choose Form Fields and/or Buttons) Other form navigation tips: Tab (To move to next field) Shift + Tab (To move to previous field) Enter (To activate drop-down box) Alt + Down Arrow (Show items in combo box or list box) Up/Down Arrows (To navigate between drop-down box options) Spacebar (To select radio buttons) | |
| Verify that required fields are identifed and that there is proper error handling. | 3.3.1 3.3.2 3.3.3 Sufficient information is provided for filling out forms, identifying required fields and correcting errors. | Fill out a form and test required fields or validated fields for proper error handling. | Same as above | |
| Verify that tables are marked up properly | 1.3.1 Data tables have simple structure. Information, structure, and relationships conveyed through presentation can be programmatically determined | Check the tables list to be sure that the table is named and that NVDA correctly interprets the number of columns and rows. Move around the cells and make sure that for each cell the correct column header, cell content, and column number is announced.
| T (To move to next Table) Ins + Down Arrow to begin reading table Ctrl + Alt + Right Arrow (To read next cell) Ctrl + Alt + Left Arrow (To read previous cell) Ctrl + Alt + Up Arrow (To read cell above) Ctrl + Alt + Down Arrow (To read cell below) |