Georgia Tech Research Institute
 
Accessibility Assistant

Accessibility Assistant

Issues

Indicator Lights (1 of 4)

Issue: Information conveyed by indicator lights is not available to all users.

A user in a wheelchair, using a front approach to a kiosk, is unable to see an illuminated indicator light because it is placed on the top of the machine, out of his field of view.

Indicator lights depend on user vision to communicate information. Therefore, the information conveyed by indicator lights is not accessible to some users with visual impairments. Furthermore, the placement of indicator lights in certain locations on a kiosk may make it difficult for users in wheelchairs to see the lights. Additionally, indicator lights are not well suited to conveying complex information, and attempting to convey complex information via indicator lights may cause confusion for users, especially for users with cognitive impairments.

Populations Impacted: Users who are blind; users with low vision; users with lower mobility impairments; users with cognitive impairments.

Potential Solutions:
  • Place indicator lights so that they are visible for both seated and standing users. When placing indicator lights, consider the viewing angle of users who are accessing the machine from wheelchairs, and avoid placing lights in locations that are only visible from a standing position.

  • A user in a wheelchair, using a front approach to a kiosk, is able to see an illuminated indicator light because it is placed on the front of the machine, within his field of view.
  • Provide a redundant alternative to vision that conveys the same information that is conveyed visually. Providing audio output that communicates the same information that indicator lights convey will increase accessibility for users who cannot see the indicator lights due to visual impairments or due to the position from which they are using the machine. Simple audio output such as beeps can be used to indicate status, but the sounds must be recognizable and distinguishable to be effective. Voice output should be used to convey more detailed information.

  • Avoid communicating complex information via indicator lights. Indicator lights are well suited for conveying simple information that can be communicated by the presence or absence of a light. Using indicator lights to convey more complex information (for example, by requiring users to discriminate between flash rates or count a sequence of flashes) should be avoided. Complex information should be presented by means of text, graphics, or voice output.

Applicable Guidelines:
ADA-ABA - 707.5
Section 508 - 1194.31(a), 1194.31(b)
HFDS - 5.11.1, 5.1.2, 5.11.6, 5.11.8, 8.18.3.3