Functional Accessibility Requirements

Table of contents

  1. Web
  2. Non-web documents
  3. Software

    9. Web

    9.2.19 Three flashes or below threshold

    Where ICT is a web page, it shall satisfy WCAG 2.0 Success Criterion 2.3.1 Three Flashes or Below Threshold.

    WCAG 2.0 success criterion: Three Flashes or Below Threshold

    Web pages do not contain anything that flashes more than three times in any one second period, or the flash is below the general flash and red flash thresholds.

    NOTE: This success criterion is applicable to all content on the Web page (whether or not there is an alternate accessible version of the content) since any part of a document that does not meet this success criterion can interfere with a user's ability to use the whole page (including a link to the alternate version).

    10. Non-web documents

    10.2.19 Three flashes or below threshold

    Where ICT is a non-web document, it shall satisfy the success criterion in Table 10.19.

    Table 10.19: Document success criterion: Three flashes or below threshold

    Documents do not contain anything that flashes more than three times in any one second period, or the flash is below the general flash and red flash thresholds.

    NOTE 1: This success criterion is applicable to all content in the document (whether or not there is an alternate accessible version of the document) since any part of a document that does not meet this success criterion can interfere with a user's ability to use the whole document (including a link to the alternate version).

    NOTE 2: This success criterion is identical to the WCAG 2.0 Success Criterion 2.3.1 Three Flashes or Below Threshold replacing "Web pages" with "documents", "the whole page" with "the whole document", "the Web page" with "the document" and removing "See Conformance Requirement 5: Non-Interference" and with note 2 above re-drafted to avoid the use of the word "must".

    11. Software

    11.2.1 Non-Web software success criteria (excluding closed functionality)

    11.2.1.19 Three flashes or below threshold

    Where ICT is non-web software that provides a user interface, it shall satisfy the success criterion in Table 11.19.

    Table 11.19: Software success criterion: Three flashes or below threshold

    Software does not contain anything that flashes more than three times in any one second period, or the flash is below the general flash and red flash thresholds.

    NOTE 1: This success criteria is applicable to all content in the software (whether or not there is an alternate accessible mode of operation of the software) since any part of a software that does not meet this success criterion can interfere with a user's ability to use the whole software (including a user interface element that enables the user to activate the alternate accessible mode of operation).

    NOTE 2: This success criterion is identical to the WCAG 2.0 Success Criterion 2.3.1 Three Flashes or Below Threshold replacing "Web pages" with "software", "the whole page" with "the whole software", "the Web page" with "the software" and removing "See Conformance Requirement 5: Non-Interference" and with note 1 above re-drafted to avoid the use of the word "must".

    11.2.2 Non-Web software requirements (closed functionality)

    11.2.2.2 Audio-only and video-only (pre-recorded)

    11.3.2 Accessibility services

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