Individuals who use screen reading software can find it hard to hear the speech output if there is other audio playing at the same time. This difficulty is exacerbated when the screen reader's speech output is software based (as most are today) and is controlled via the same volume control as the sound. Therefore, it is important that the user - be able to turn off the background sound. + be able to turn off the background sound.
Having control of the volume includes being able to reduce its volume to zero. Muting the system volume is not "pausing or stopping" the autoplay audio. Both the "pause or stop" and control of audio volume need to be independent of the overall system volume.
-Playing audio automatically when landing on a page may affect a screen reader user's ability to find the mechanism to stop it because they navigate by listening and automatically started sounds might interfere with that navigation. Therefore, we discourage the practice of automatically starting sounds (especially if they last more than 3 seconds), - and encourage that the sound be + and encourage that the sound be started by an action initiated by the user after they reach the page, rather than requiring - that the sound be + that the sound be stopped by an action of the user after they land on the page.
-See also - 1.4.7: Low or No Background Audio. -
- - +See also 1.4.7 Low or No Background Audio.
+In the context of this Success Criterion, "plays automatically" broadly refers to audio that is not started/played as a direct result of a user's intentional activation. For example, not selecting a link or button.
The intent of this Success Criterion is to avoid distracting users during their interaction with a Web page.
- + +In the context of this Success Criterion, "starts automatically" broadly refers to animations/updates + that are not the direct result of a user's intentional activation, for example, selecting a link or button.
+"Moving, blinking and scrolling" refers to content in which the visible content conveys a sense of motion. Common examples include motion pictures, synchronized media presentations, animations, real-time games, and scrolling stock tickers. "Auto-updating" refers to content that updates or disappears based on a preset time interval. Common time-based - content includes audio, automatically updated weather information, news, stock price + content includes automatically updated weather information, news, stock price updates, and auto-advancing presentations and messages. The requirements for moving, blinking and scrolling content and for auto-updating content are the same except that:
- +Content that moves or auto-updates can be a barrier to anyone who has trouble reading stationary text quickly as well as anyone who has trouble tracking moving objects. It can also cause problems for screen readers.
- +Moving content can also be a severe distraction for some people. Certain groups, particularly those with attention deficit disorders, find blinking content distracting, making it difficult for them to concentrate on other parts of the Web page. Five seconds was chosen because it is long enough to get a user's attention, but not so long that a user cannot wait out the distraction if necessary to use the page.
- +Content that is paused can either resume in real-time or continue playing from the point in the presentation where the user left off.
- +Pausing and resuming where the user left off is best for users who want to pause to read content and works best when the content is not associated with a real-time event or status.
-See - 2.2.1: Timing Adjustable for additional requirements related to time-limits for reading. -
- +See 2.2.1: Timing Adjustable for additional requirements related to time-limits for reading and interactions.
Pausing and jumping to current display (when pause is released) is better for information that is real-time or "status" in nature. For example, weather radar, a stock ticker, a traffic camera, or an auction timer, would present misleading information if a pause caused it to display old information when the content was restarted.
-Hiding content would have the same result as pausing and jumping to current display - (when pause is released). -
- +Hiding content would have the same result as pausing and jumping to current display (when pause is released).
For a mechanism to be considered "a mechanism for the user to pause," it must provide the user with a means to pause that does not tie up the user or the focus so that the page cannot be used. The word "pause" here is meant in the sense of a "pause @@ -110,58 +88,58 @@
It is important to note that the terms "blinking" and "flashing" can sometimes refer - to the same content. -
- + +This Success Criterion is specifically concerned with moving, blinking, scrolling, and + auto-updating visual content. For audio content that starts automatically, refer to 1.4.2 Audio Control.
+Moving, blinking, scrolling content that starts automatically because of a general user interaction (such as focusing/hovering over an element, + or scrolling the page), rather than as a result of an intentional activation (such as activating a button), + and which doesn't provide provide a way to Pause, Stop, or Hide, will fail this Criterion, and potentially + 2.3.3 Animation from Interaction.
+It is important to note that the terms "blinking" and "flashing" can sometimes refer to the same content.
+"Flashing" content that starts automatically will need to be evaluated against 2.3.2 Three Flashes + and 2.3.1 Three Flashes or Below Threshold. +
+The intent of this Success Criterion is to allow users to prevent animation from being displayed on Web pages. Some users experience distraction or nausea from animated content. For example, if scrolling a page causes elements to move (other than the essential movement associated with scrolling) it can trigger vestibular disorders. Vestibular (inner ear) disorder reactions include dizziness, nausea and headaches. Another animation that is often non-essential is parallax scrolling. Parallax scrolling occurs when backgrounds move at a different rate to foregrounds. Animation that is essential to the functionality or information of a web page is allowed by this Success Criterion.
-"Animation from interactions" applies when a user’s interaction initiates non-essential animation. In contrast, 2.2.2 Pause, Stop, Hide applies when the web page initiates animation.
+"Animation from interactions" applies when a user’s interaction initiates non-essential animation. In contrast, 2.2.2 Pause, Stop, Hide applies when the web page initiates animation "automatically" that is not in response to an intentional user activation. There may be situations where a particular animation may fail both Success Criteria.
The impact of animation on people with vestibular disorders can be quite severe. Triggered reactions include nausea, migraine headaches, and potentially needing bed rest to recover.
How can a website reduce the chances of triggering a vestibular disorder? Choose any one of the following solutions. Avoid using unnecessary animation. Provide a control for users to turn off non-essential animations from user interaction. Take advantage of the reduce motion feature in the user agent or operating system.
- +What about movement caused by a user scrolling a page? Moving new content into the viewport is essential for scrolling. The user controls the essential scrolling movement so it is allowed. Only add non-essential animation to the scrolling interaction in a responsible way. Always give users the ability to turn off unnecessary movement.