Accessibility testing with screen readers

These instructions are intended for the use of a screen reader in the self-assessment of accessibility.

Screen readers, or screen reading software, are applications that act as an interface between the operating system, applications and the user. Screen readers read the text on the screen and repeat it through the voice synthesiser or convert it into Braille. This makes it possible for, for example, visually impaired and blind users to use the computer. Screen readers are controlled by keyboard commands which correspond to the desired functions, for example, navigating to a heading or form field on a web page.

As screen reader users navigate with keyboard commands without any visual feedback, so the content of web applications must be correctly defined semantically and programmatically. A person using a screen reader often uses headings or links to go through the site. From the point of view of testing, the most important thing is to be able to navigate the website. It is recommended that all testers have the same settings on, at least per screen reader.

    General information about screen readers

    The most common screen readers are NVDA and JAWS for Windows and VoiceOver for Mac. Linux comes with Orca, which is not included in these instructions. Read more about the Orca screen reader in the GNOME instructions.

    NVDA is free of charge. A JAWS licence is expensive, but many visually impaired people use it in studies and work, as Kela regards it as an aid and reimburses it. In the free version, the session length is limited to 40 minutes. 

    In a Desktop environment, NVDA is more common than VoiceOver, so testing with NVDA is a priority. Therefore, the PC + Chrome/Firefox + NVDA combination should be prioritised where possible. VoiceOver often reads things differently than NVDA. Mac users can access the NVDA using the University’s virtual desktop.

    On mobile devices, iOS + Safari + VoiceOver is the most common and recommended combination for testing, but these instructions do not include the mobile VoiceOver instructions. 

    There are small differences between screen readers and the best functionality is guaranteed by the combinations below (operating system - screen reader - browser):

    • Windows - NVDA - Chrome
    • Windows - JAWS - Chrome
    • macOS - VoiceOver - Safari
    • Android - Talkback - Chrome
    • iOS - VoiceOver - Safari

    Deployment of NVDA

    Installation (Windows)

    NVDA can be installed from the Software Center on the University's centrally managed Windows computer or from NVDA’s official website.

    Access via VDI (Mac and Linux)

    NVDA is installed on the University’s virtual desktop, i.e. on the VDI computer Windows 10 for staff. The programme can be found in the start menu. For instructions on using the VDI computer, see the IT Helpdesk’s instructions page.

    Note! Using NVDA on a VDI computer requires, in practice, a long keyboard made for Windows or, alternatively, a long Mac keyboard where the numpad key 0 corresponds to the Windows insert key. The insert key or numpad zero is used as the NVDA button, Caps Lock does not work on the virtual machine in this use. Other exceptions may also occur, especially with respect to keyboard commands.

    NVDA’s general settings and functions

    NVDA = insertkey by default, can be changed in the settings. 

    NVDA opens in the notification area, which is typically at the bottom right of the screen. By right-clicking on the icon with the capital letter N, you can access, for example, the programme settings.

    NVDA’s general settings and functions

    • NVDA + 1 Training mode 
      Sets the training mode on/off. 
      Clicking the buttons shows their functionalities without executing them. You can practise using NVDA safely.
    • NVDA + Q Closing NVDA 
    • Preferences → Settings → Keyboard → Select NVDA Modifier Keys Changing the NVDA key
    • The only default is insert.
    • NVDA + S Quiet mode
      Switches between speech modes (speech, silent, beeps).
    • Preferences → Settings → Speech Speech settings
      Adjust the speaking rate, voice synthesiser sound and volume.
    • Tools → Speech viewer Screen reader speech review in text format
      Displays the screen reader speech in text format. Helps the sighted user in testing.
    • Preferences → Settings → Vision→ Enable Highlighting Visual highlighting
      Displays the visual focus of the user’s location on the page.

    Navigating the site with NVDA

    NVDA = insertkey by default, can be changed in the settings.
    The Shift + key combination navigates to the previous element corresponding to the combination on the page unless otherwise stated.

    • Down arrow Read next row 
    • Up arrow Read previous row 
    • NVDA + up arrow Re-read current row 
    • Shift Discontinue reading current line 
    • NVDA Stop reading current line 
    • Tab Read the following functional element (link, button, form field, etc.) 
    • Read next heading 
    • Read next table 
    • Read next landmark 
    • G Read next graphic

    Read more

    Deployment of VoiceOver

    Mac computers come with the VoiceOver screen reader included in the operating system; there are practically no alternative programmes.

    However, NVDA is installed on the University’s Windows 10 for staff computer in the virtual workstation environment, so NVDA can also be used on a Mac. Instructions on how to use the virtual workstation environment can be found on the IT Helpdesk instructions site.

    It is recommended to use Safari as a browser with VoiceOver, but Chrome also works mainly well.

    VoiceOver’s general settings and functions

    VO = Control + Option (default)
    Since the F1–F12 keys are often also used, for example, to adjust the volume and brightness of the display, it may be necessary to press the Fn key in order for the F1–F12 keys to work properly.

    • Command + F5 or Command + Fingerprint button quickly three times or Fn + Command + F5 (Short separate keyboard)
      Turning off and on 
      Laptop keyboard or long keyboard with a separate numpad 
    • Control 
      Mute speech
    • VO + F8 
      Opening the VoiceOver tool when VoiceOver is on
      The VoiceOver tool allows you to change the settings related to the screen reader. The tool can be found in the Tools folder of the Application folder. 
    • General → Keys to use as the VoiceOver modifier Change the modifier key
      Default Control + Option, also Caps Lock as an option
    • VO + ; locking and unlocking the VO modifier key
      After locking the VO modifier key, the key commands can be used without clicking VO
    • Speech → Mute speech
      Quiet Mode
    • Visuals → Panels and Menus → Show caption panel Reviewing screen reader speech in text format.
      Displays the screen reader speech in text format. Helps the sighted user in testing.
    • Speech → Voices Speech: voice, speed and language
    • Visuals → Cursors → Show VoiceOver Cursor Visual focus.
      Displays the visual focus of the user’s location on the page. VoiceOver Cursor Magnification (Sve: Förstoring av VoiceOver-pekaren / Eng: VoiceOver Cursor Magnification) should be kept minimum.
    • VO + Opening the rotor
      esc Closing the rotor
      right arrow Go to next window
      left arrow Go to previous window
      up or down arrow scrolling down the list
      enter selecting an item
      The rotor can be used to view, for example, different element lists, such as web page or text file headings.

    Website navigation

    VO = Control + Option (default)
    previous element = an addition in key combination Shift

    • VO + Right or left arrow
      Go through all the content on the website
    • Tab
      Read the following functional element (link, button, form field, etc.)
    • VO + Space
      Open link/double click
    • VO + Shift + down arrow
      Go to content
    • VO + Shift + up arrow
      Exit content
    • VO + Command +
      Read next heading
    • VO + Command + L
      Read next link 
    • VO + Command + G
      Read next graphic
    • VO + Command + J
      Read next section of the form
    • VO + Command + X
      Read next list 


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