Hardware Self Contained, Closed Products
checklist

Checkpoint 4.1: Volume control

For devices with audio output, provide the ability to adjust the volume. Provide a function to reset the volume to the default level after every use.


Rationale

When a product uses audio output to provide important information, someone with a hearing impairment can have difficulty hearing the information if they are in a public area. Users need to be able to adjust the volume so they can hear the information. If the product is in an environment with a high noise level, users may need to adjust the volume so the voice output can be heard.


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Required development techniques

The following techniques are the minimum required to meet Checkpoint 4.1 from the IBM Hardware Self Contained, Closed Products Accessibility Checklist:

  • Provide a physical volume control on the system which can be easily reached or a software interface for adjusting the volume.
  • The volume control should provide amplification up to a level of at least 65 dB. Where the ambient noise level of the environment is above 45 dB, a volume gain of at least 20 dB above the ambient level should be available.
  • Provide a method to automatically reset the volume to the default level after use.

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Recommended development techniques

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

Provide visual and non-visual indicators when the volume is in the off position.

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Required test techniques

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

Tools

A sound meter is needed to test this checkpoint.

Techniques

One or more of the following techniques are required to verify this checkpoint:
Action Result
1. Verify that there is a physical volume control on the system.

Verify through inspection.		 Pass:
  • System has a volume control.

Fail:
  • System has no volume control.
2. Verify that there is a software interface for adjusting the volume.

Verify through inspection of the specification and software test cases.		 Pass:
  • System specification indicates there is a software interface for adjusting the volume.
  • Software test case sucessfully demonstrates that the volume can be adjusted using software.

Fail:
  • System specification fails to indicate there is a software interface for adjusting the volume.
  • Software test case fails to demonstrates that the volume can be adjusted using software.
3. Verify that the volume can be reset to the default level.

Verify by using a sound level meter.		 Pass:
  • Sound level returns to the default level.

Fail:
  • Sound level does not return to the default level.

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©2009 IBM Corporation

Last updated September 01, 2009.


Checkpoint 3.2

Hardware Self Contained,
Closed Products checklist

Checkpoint 4.2