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      <title>Detailed View for rule: Avoid causing the screen to flicker</title>
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               <td valign="top" nowrap="true" class="name">Avoid causing the screen to flicker</td>
               <td valign="top" nowrap="true" class="compatibility">&nbsp;</td>
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                  Section 508 1194.22(j); 
                  
                  WAI
                  
                  / 
                  
                  WCAG
                  
                  1.0 checkpoint 7.1
                  
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               <td valign="top" colspan="2" class="description"><b>Issue Description</b><br>
                  
                  <p>
                     The page contains a graphic object that may cause the
                     screen to flicker. 
                     <br>
                     Make sure the page does not contain an animated object
                     with a refresh rate of between 2 to 55 frames per second.
                     
                  </p>
                  
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               <td valign="top" colspan="2" class="description"><b>How to check</b>
                  
                  <p>
                     Make sure no animated object has a refresh rate of between
                     2 to 55 frames per second. In other words, make sure no
                     image repeatedly flashes or changes from dark to light from
                     2 and 55 times per second.
                     
                  </p>
                  
                  
                  <p>
                     If you need to use the animated object, increase its
                     refresh rate to more than 55 frames per second or change
                     its colors to reduce the flickering effect.
                     
                  </p>
                  
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               <td valign="top" colspan="2" class="description"><b>Issue Explanation</b><br>
                  
                  <p>
                     A flickering or flashing screen may cause seizures in users
                     with photosensitive epilepsy. As a result, content
                     developers should avoid causing the screen to flicker.
                     
                  </p>
                  
                  
                  <p>
                     Seizures can be triggered by a light flickering or flashing
                     2 to 55 times per second, with peak sensitivity at 20
                     flashes per second with quick changes from dark to light.
                     
                  </p>
                  
                  
                  <p>
                     Here are HTML elements that may cause flickering:
                     
                  </p>
                  
                  
                  <ul>
                     
                     <li>
                        SCRIPT: A scripting language can be used to create
                        animations
                        
                     </li>
                     
                     
                     <li>
                        OBJECT: An OBJECT can contain movies, animated GIFs, or
                        animated Java applets
                        
                     </li>
                     
                     
                     <li>
                        EMBED: This tag is usually used to include movies on the
                        page
                        
                     </li>
                     
                     
                     <li>
                        APPLET: Java applets can display animations
                        
                     </li>
                     
                  </ul>
                  
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