Hardware checklist

Checkpoint 5.1: System sounds

Provide an interface so that use of system sounds can be known to software.


Many systems use the speaker to announce warnings or errors to the user. A user who is deaf or hard of hearing will not be able to hear and respond to the warning. Systems need to provide an interface so that software can provide an alternative method of providing the information.

Required development techniques

The following technique is the minimum required to meet checkpoint 5.1 from the IBM Hardware Accessibility Checklist:

Recommended development techniques

The above techniques are required; the following technique is recommended to enhance accessibility:

Provide a visual equivalent of the system sound such as displaying the warning on the screen. If you flash the screen to indicate an alert has occurred, avoid flash rates between 2 Hz and 55 Hz that may affect people with photo sensitive epilepsy.

Required test techniques

Test the hardware to ensure that it complies with accessibility requirements.


No tools are needed to test this checkpoint:


One or more of the following techniques are required to verify this checkpoint:
Action Result


Verify that there is an interface between system sounds and software through inspection of the specification and software test cases.



©2009 IBM Corporation

Last updated on July 22, 2009.