Techniques for WCAG 2.0 Techniques and Failures for Web Content Accessibility Guidelines 2.0 W3C Working Group Note 7 October 2016 This version: https://www.w3.org/TR/2016/NOTE-WCAG20-TECHS-20161007/ Latest version: https://www.w3.org/TR/WCAG20-TECHS/ Previous version: https://www.w3.org/TR/2016/NOTE-WCAG20-TECHS-20160317/ Editors: Michael Cooper, W3C Andrew Kirkpatrick, Adobe Systems Inc. Joshue O Connor, InterAccess Previous Editors: Loretta Guarino Reid (until May 2013 while at Google, Inc.) Gregg Vanderheiden (until May 2013 while at Trace R&D Center, University of Wisconsin-Madison) Ben Caldwell (until September 2010 while at Trace R&D Center, University of Wisconsin-Madison) Wendy Chisholm (until July 2006 while at W3C) John Slatin (until June 2006 while at Accessibility Institute, University of Texas at Austin) This document is also available in these non-normative formats: Single file version Single file diff-marked version showing revisions since 17 March 2015 , and Alternate Versions of Techniques for WCAG 2.0 , Copyright © 2016 W3C ® ( MIT , ERCIM , Keio , Beihang ). W3C liability , trademark and document use rules apply. Abstract This Techniques for WCAG 2.0 document provides guidance for web content authors and evaluators on meeting Web Content Accessibility Guidelines (WCAG) 2.0 [WCAG20] success criteria. It is part of a series of documents published by the W3C Web Accessibility Initiative (WAI) to support WCAG 2.0. For an introduction to WCAG, supporting technical documents, and educational material, see Web Content Accessibility Guidelines (WCAG) Overview . Techniques are informative—that means they are not required. The basis for determining conformance to WCAG 2.0 is the success criteria from the WCAG 2.0 standard —not the techniques. For important information about techniques, please see the Understanding Techniques for WCAG Success Criteria section of Understanding WCAG 2.0. Techniques for WCAG 2.0 is not intended to be used as a stand-alone document. Instead, it is expected that content authors will usually use How to Meet WCAG 2.0: A customizable quick reference to read the WCAG success criteria, and follow links from there to specific topics in Understanding WCAG 2.0 and to specific techniques. Status of This Document This document is no longer maintained. For the latest version, see https://www.w3.org/WAI/WCAG22/Techniques/ . This section describes the status of this document at the time of its publication. Other documents may supersede this document. A list of current W3C publications and the latest revision of this technical report can be found in the W3C technical reports index at https://www.w3.org/TR/ . This is a Working Group Note "Techniques for WCAG 2.0". These techniques are produced by the Web Content Accessibility Guidelines Working Group to provide guidance about how to conform to the Web Content Accessibility Guidelines (WCAG) 2.0 Recommendation . Techniques are referenced from Understanding WCAG 2.0 and How to Meet WCAG 2.0 . Please note that the contents of this document are informative (they provide guidance), and not normative (they do not set requirements for conforming to WCAG 2.0). WCAG 2.0 Techniques was previously published on 11 December 2008 as a Working Group Note and updated 14 October 2010, 3 January 2012, 5 September 2013, 3 March 2014, 8 April 2014, 16 September 2014, 26 February 2015, and 17 March 2016. This new version updates the support information provided for WCAG 2.0. Note that WCAG 2.0 itself remains unchanged, only the informative support materials have been updated. Primary changes include clarifications based on input from the public and translators. Changes in this version include clarifications in techniques G136: Providing a link at the beginning of a nonconforming Web page that points to a conforming alternate version , ARIA2: Identifying a required field with the aria-required property (ARIA) , and F68: Failure of Success Criterion 4.1.2 due to a user interface control not having a programmatically determined name . The changes are highlighted in the diff-marked version . The Working Group requests that any comments be made using the options documented in Instructions for Commenting on WCAG 2.0 Documents . If this is not possible, comments can also be sent to [email protected] . The archives for the public comments list are publicly available. Comments received on this document may be addressed in future versions of this document, or in another manner. Archives of the WCAG WG mailing list discussions are also publicly available, and future work undertaken by the Working Group may address comments received on this document. Materials from the public to assist in documenting techniques are particularly welcomed. Please use the Techniques Submission Form to submit techniques. This document has been produced as part of the W3C Web Accessibility Initiative (WAI). The goals of the WCAG Working Group are discussed in the WCAG Working Group charter . The WCAG Working Group is part of the WAI Technical Activity . Publication as a Working Group Note does not imply endorsement by the W3C Membership. This is a draft document and may be updated, replaced or obsoleted by other documents at any time. It is inappropriate to cite this document as other than work in progress. This document was produced by a group operating under the 5 February 2004 W3C Patent Policy . W3C maintains a public list of any patent disclosures made in connection with the deliverables of the group; that page also includes instructions for disclosing a patent. An individual who has actual knowledge of a patent which the individual believes contains Essential Claim(s) must disclose the information in accordance with section 6 of the W3C Patent Policy . This document is governed by the 1 September 2015 W3C Process Document . Table of Contents Abstract Status of This Document Introduction to Techniques for WCAG 2.0 General Techniques (all General Techniques on one page) G1: Adding a link at the top of each page that goes directly to the main content area G4: Allowing the content to be paused and restarted from where it was paused G5: Allowing users to complete an activity without any time limit G8: Providing a movie with extended audio descriptions G9: Creating captions for live synchronized media G10: Creating components using a technology that supports the accessibility API features of the platforms on which the user agents will be run to expose the names and roles, allow user-settable properties to be directly set, and provide notification of changes G11: Creating content that blinks for less than 5 seconds G13: Describing what will happen before a change to a form control that causes a change of context to occur is made G14: Ensuring that information conveyed by color differences is also available in text G15: Using a tool to ensure that content does not violate the general flash threshold or red flash threshold G17: Ensuring that a contrast ratio of at least 7:1 exists between text (and images of text) and background behind the text G18: Ensuring that a contrast ratio of at least 4.5:1 exists between text (and images of text) and background behind the text G19: Ensuring that no component of the content flashes more than three times in any 1-second period G21: Ensuring that users are not trapped in content G53: Identifying the purpose of a link using link text combined with the text of the enclosing sentence G54: Including a sign language interpreter in the video stream G55: Linking to definitions G56: Mixing audio files so that non-speech sounds are at least 20 decibels lower than the speech audio content G57: Ordering the content in a meaningful sequence G58: Placing a link to the alternative for time-based media immediately next to the non-text content G59: Placing the interactive elements in an order that follows sequences and relationships within the content G60: Playing a sound that turns off automatically within three seconds G61: Presenting repeated components in the same relative order each time they appear G62: Providing a glossary G63: Providing a site map G64: Providing a Table of Contents G65: Providing a breadcrumb trail G68: Providing a short text alternative that describes the purpose of live audio-only and live video-only content G69: Providing an alternative for time based media G70: Providing a function to search an online dictionary G71: Providing a help link on every Web page G73: Providing a long description in another location with a link to it that is immediately adjacent to the non-text content G74: Providing a long description in text near the non-text content, with a reference to the location of the long description in the short description G75: Providing a mechanism to postpone any updating of content G76: Providing a mechanism to request an update of the content instead of updating automatically G78: Providing a second, user-selectable, audio track that includes audio descriptions G79: Providing a spoken version of the text G80: Providing a submit button to initiate a change of context G81: Providing a synchronized video of the sign language interpreter that can be displayed in a different viewport or overlaid on the image by the player G82: Providing a text alternative that identifies the purpose of the non-text content G83: Providing text descriptions to identify required fields that were not completed G84: Providing a text description when the user provides information that is not in the list of allowed values G85: Providing a text description when user input falls outside the required format or values G86: Providing a text summary that can be understood by people with lower secondary education level reading ability G87: Providing closed captions G88: Providing descriptive titles for Web pages G89: Providing expected data format and example G90: Providing keyboard-triggered event handlers G91: Providing link text that describes the purpose of a link G92: Providing long description for non-text content that serves the same purpose and presents the same information G93: Providing open (always visible) captions G94: Providing short text alternative for non-text content that serves the same purpose and presents the same information as the non-text content G95: Providing short text alternatives that provide a brief description of the non-text content G96: Providing textual identification of items that otherwise rely only on sensory information to be understood G97: Providing the first use of an abbreviation immediately before or after the expanded form G98: Providing the ability for the user to review and correct answers before submitting G99: Providing the ability to recover deleted information G100: Providing a short text alternative which is the accepted name or a descriptive name of the non-text content G101: Providing the definition of a word or phrase used in an unusual or restricted way G102: Providing the expansion or explanation of an abbreviation G103: Providing visual illustrations, pictures, and symbols to help explain ideas, events, and processes G105: Saving data so that it can be used after a user re-authenticates G107: Using "activate" rather than "focus" as a trigger for changes of context G108: Using markup features to expose the name and role, allow user-settable properties to be directly set, and provide notification of changes G110: Using an instant client-side redirect G111: Using color and pattern G112: Using inline definitions G115: Using semantic elements to mark up structure G117: Using text to convey information that is conveyed by variations in presentation of text G120: Providing the pronunciation immediately following the word G121: Linking to pronunciations G123: Adding a link at the beginning of a block of repeated content to go to the end of the block G124: Adding links at the top of the page to each area of the content G125: Providing links to navigate to related Web pages G126: Providing a list of links to all other Web pages G127: Identifying a Web page's relationship to a larger collection of Web pages G128: Indicating current location within navigation bars G130: Providing descriptive headings G131: Providing descriptive labels G133: Providing a checkbox on the first page of a multipart form that allows users to ask for longer session time limit or no session time limit G134: Validating Web pages G135: Using the accessibility API features of a technology to expose names and roles, to allow user-settable properties to be directly set, and to provide notification of changes G136: Providing a link at the beginning of a nonconforming Web page that points to a conforming alternate version G138: Using semantic markup whenever color cues are used G139: Creating a mechanism that allows users to jump to errors G140: Separating information and structure from presentation to enable different presentations G141: Organizing a page using headings G142: Using a technology that has commonly-available user agents that support zoom G143: Providing a text alternative that describes the purpose of the CAPTCHA G144: Ensuring that the Web Page contains another CAPTCHA serving the same purpose using a different modality G145: Ensuring that a contrast ratio of at least 3:1 exists between text (and images of text) and background behind the text G146: Using liquid layout G148: Not specifying background color, not specifying text color, and not using technology features that change those defaults G149: Using user interface components that are highlighted by the user agent when they receive focus G150: Providing text based alternatives for live audio-only content G151: Providing a link to a text transcript of a prepared statement or script if the script is followed G152: Setting animated gif images to stop blinking after n cycles (within 5 seconds) G153: Making the text easier to read G155: Providing a checkbox in addition to a submit button G156: Using a technology that has commonly-available user agents that can change the foreground and background of blocks of text G157: Incorporating a live audio captioning service into a Web page G158: Providing an alternative for time-based media for audio-only content G159: Providing an alternative for time-based media for video-only content G160: Providing sign language versions of information, ideas, and processes that must be understood in order to use the content G161: Providing a search function to help users find content G162: Positioning labels to maximize predictability of relationships G163: Using standard diacritical marks that can be turned off G164: Providing a stated time within which an online request (or transaction) may be amended or canceled by the user after making the request G165: Using the default focus indicator for the platform so that high visibility default focus indicators will carry over G166: Providing audio that describes the important video content and describing it as such G167: Using an adjacent button to label the purpose of a field G168: Requesting confirmation to continue with selected action G169: Aligning text on only one side G170: Providing a control near the beginning of the Web page that turns off sounds that play automatically G171: Playing sounds only on user request G172: Providing a mechanism to remove full justification of text G173: Providing a version of a movie with audio descriptions G174: Providing a control with a sufficient contrast ratio that allows users to switch to a presentation that uses sufficient contrast G175: Providing a multi color selection tool on the page for foreground and background colors G176: Keeping the flashing area small enough G177: Providing suggested correction text G178: Providing controls on the Web page that allow users to incrementally change the size of all text on the page up to 200 percent G179: Ensuring that there is no loss of content or functionality when the text resizes and text containers do not change their width G180: Providing the user with a means to set the time limit to 10 times the default time limit G181: Encoding user data as hidden or encrypted data in a re-authorization page G182: Ensuring that additional visual cues are available when text color differences are used to convey information G183: Using a contrast ratio of 3:1 with surrounding text and providing additional visual cues on focus for links or controls where color alone is used to identify them G184: Providing text instructions at the beginning of a form or set of fields that describes the necessary input G185: Linking to all of the pages on the site from the home page G186: Using a control in the Web page that stops moving, blinking, or auto-updating content G187: Using a technology to include blinking content that can be turned off via the user agent G188: Providing a button on the page to increase line spaces and paragraph spaces G189: Providing a control near the beginning of the Web page that changes the link text G190: Providing a link adjacent to or associated with a non-conforming object that links to a conforming alternate version G191: Providing a link, button, or other mechanism that reloads the page without any blinking content G192: Fully conforming to specifications G193: Providing help by an assistant in the Web page G194: Providing spell checking and suggestions for text input G195: Using an author-supplied, highly visible focus indicator G196: Using a text alternative on one item within a group of images that describes all items in the group G197: Using labels, names, and text alternatives consistently for content that has the same functionality G198: Providing a way for the user to turn the time limit off G199: Providing success feedback when data is submitted successfully G200: Opening new windows and tabs from a link only when necessary G201: Giving users advanced warning when opening a new window G202: Ensuring keyboard control for all functionality G203: Using a static text alternative to describe a talking head video G204: Not interfering with the user agent's reflow of text as the viewing window is narrowed G205: Including a text cue for colored form control labels G206: Providing options within the content to switch to a layout that does not require the user to scroll horizontally to read a line of text HTML and XHTML Techniques (all HTML and XHTML Techniques on one page) H2: Combining adjacent image and text links for the same resource H4: Creating a logical tab order through links, form controls, and objects H24: Providing text alternatives for the area elements of image maps H25: Providing a title using the title element H28: Providing definitions for abbreviations by using the abbr element H30: Providing link text that describes the purpose of a link for anchor elements H32: Providing submit buttons H33: Supplementing link text with the title attribute H34: Using a Unicode right-to-left mark (RLM) or left-to-right mark (LRM) to mix text direction inline H35: Providing text alternatives on applet elements H36: Using alt attributes on images used as submit buttons H37: Using alt attributes on img elements H39: Using caption elements to associate data table captions with data tables H40: Using description lists H42: Using h1-h6 to identify headings H43: Using id and headers attributes to associate data cells with header cells in data tables H44: Using label elements to associate text labels with form controls H45: Using longdesc H46: Using noembed with embed H48: Using ol, ul and dl for lists or groups of links H49: Using semantic markup to mark emphasized or special text H51: Using table markup to present tabular information H53: Using the body of the object element H54: Using the dfn element to identify the defining instance of a word H56: Using the dir attribute on an inline element to resolve problems with nested directional runs H57: Using language attributes on the html element H58: Using language attributes to identify changes in the human language H59: Using the link element and navigation tools H60: Using the link element to link to a glossary H62: Using the ruby element H63: Using the scope attribute to associate header cells and data cells in data tables H64: Using the title attribute of the frame and iframe elements H65: Using the title attribute to identify form controls when the label element cannot be used H67: Using null alt text and no title attribute on img elements for images that AT should ignore H69: Providing heading elements at the beginning of each section of content H70: Using frame elements to group blocks of repeated material H71: Providing a description for groups of form controls using fieldset and legend elements H73: Using the summary attribute of the table element to give an overview of data tables H74: Ensuring that opening and closing tags are used according to specification H75: Ensuring that Web pages are well-formed H76: Using meta refresh to create an instant client-side redirect H77: Identifying the purpose of a link using link text combined with its enclosing list item H78: Identifying the purpose of a link using link text combined with its enclosing paragraph H79: Identifying the purpose of a link in a data table using the link text combined with its enclosing table cell and associated table header cells H80: Identifying the purpose of a link using link text combined with the preceding heading element H81: Identifying the purpose of a link in a nested list using link text combined with the parent list item under which the list is nested H83: Using the target attribute to open a new window on user request and indicating this in link text H84: Using a button with a select element to perform an action H85: Using OPTGROUP to group OPTION elements inside a SELECT H86: Providing text alternatives for ASCII art, emoticons, and leetspeak H88: Using HTML according to spec H89: Using the title attribute to provide context-sensitive help H90: Indicating required form controls using label or legend H91: Using HTML form controls and links H93: Ensuring that id attributes are unique on a Web page H94: Ensuring that elements do not contain duplicate attributes H95: Using the track element to provide captions H96: Using the track element to provide audio descriptions H97: Grouping related links using the nav element CSS Techniques (all CSS Techniques on one page) C6: Positioning content based on structural markup C7: Using CSS to hide a portion of the link text C8: Using CSS letter-spacing to control spacing within a word C9: Using CSS to include decorative images C12: Using percent for font sizes C13: Using named font sizes C14: Using em units for font sizes C15: Using CSS to change the presentation of a user interface component when it receives focus C17: Scaling form elements which contain text C18: Using CSS margin and padding rules instead of spacer images for layout design C19: Specifying alignment either to the left OR right in CSS C20: Using relative measurements to set column widths so that lines can average 80 characters or less when the browser is resized C21: Specifying line spacing in CSS C22: Using CSS to control visual presentation of text C23: Specifying text and background colors of secondary content such as banners, features and navigation in CSS while not specifying text and background colors of the main content C24: Using percentage values in CSS for container sizes C25: Specifying borders and layout in CSS to delineate areas of a Web page while not specifying text and text-background colors C27: Making the DOM order match the visual order C28: Specifying the size of text containers using em units C29: Using a style switcher to provide a conforming alternate version C30: Using CSS to replace text with images of text and providing user interface controls to switch Client-side Scripting Techniques (all Client-side Scripting Techniques on one page) SCR1: Allowing the user to extend the default time limit SCR2: Using redundant keyboard and mouse event handlers SCR14: Using scripts to make nonessential alerts optional SCR16: Providing a script that warns the user a time limit is about to expire SCR18: Providing client-side validation and alert SCR19: Using an onchange event on a select element without causing a change of context SCR20: Using both keyboard and other device-specific functions SCR21: Using functions of the Document Object Model (DOM) to add content to a page SCR22: Using scripts to control blinking and stop it in five seconds or less SCR24: Using progressive enhancement to open new windows on user request SCR26: Inserting dynamic content into the Document Object Model immediately following its trigger element SCR27: Reordering page sections using the Document Object Model SCR28: Using an expandable and collapsible menu to bypass block of content SCR29: Adding keyboard-accessible actions to static HTML elements SCR30: Using scripts to change the link text SCR31: Using script to change the background color or border of the element with focus SCR32: Providing client-side validation and adding error text via the DOM SCR33: Using script to scroll content, and providing a mechanism to pause it SCR34: Calculating size and position in a way that scales with text size SCR35: Making actions keyboard accessible by using the onclick event of anchors and buttons SCR36: Providing a mechanism to allow users to display moving, scrolling, or auto-updating text in a static window or area SCR37: Creating Custom Dialogs in a Device Independent Way SCR38: Creating a conforming alternate version for a web page designed with progressive enhancement Server-side Scripting Techniques (all Server-side Scripting Techniques on one page) SVR1: Implementing automatic redirects on the server side instead of on the client side SVR2: Using .htaccess to ensure that the only way to access non-conforming content is from conforming content SVR3: Using HTTP referer to ensure that the only way to access non-conforming content is from conforming content SVR4: Allowing users to provide preferences for the display of conforming alternate versions SVR5: Specifying the default language in the HTTP header SMIL Techniques (all SMIL Techniques on one page) SM1: Adding extended audio description in SMIL 1.0 SM2: Adding extended audio description in SMIL 2.0 SM6: Providing audio description in SMIL 1.0 SM7: Providing audio description in SMIL 2.0 SM11: Providing captions through synchronized text streams in SMIL 1.0 SM12: Providing captions through synchronized text streams in SMIL 2.0 SM13: Providing sign language interpretation through synchronized video streams in SMIL 1.0 SM14: Providing sign language interpretation through synchronized video streams in SMIL 2.0 Plain Text Techniques (all Plain Text Techniques on one page) T1: Using standard text formatting conventions for paragraphs T2: Using standard text formatting conventions for lists T3: Using standard text formatting conventions for headings ARIA Techniques (all ARIA Techniques on one page) WAI-ARIA Technology Notes ARIA1: Using the aria-describedby property to provide a descriptive label for user interface controls ARIA2: Identifying a required field with the aria-required property ARIA4: Using a WAI-ARIA role to expose the role of a user interface component ARIA5: Using WAI-ARIA state and property attributes to expose the state of a user interface component ARIA6: Using aria-label to provide labels for objects ARIA7: Using aria-labelledby for link purpose ARIA8: Using aria-label for link purpose ARIA9: Using aria-labelledby to concatenate a label from several text nodes ARIA10: Using aria-labelledby to provide a text alternative for non-text content ARIA11: Using ARIA landmarks to identify regions of a page ARIA12: Using role=heading to identify headings ARIA13: Using aria-labelledby to name regions and landmarks ARIA14: Using aria-label to provide an invisible label where a visible label cannot be used ARIA15: Using aria-describedby to provide descriptions of images ARIA16: Using aria-labelledby to provide a name for user interface controls ARIA17: Using grouping roles to identify related form controls ARIA18: Using aria-alertdialog to Identify Errors ARIA19: Using ARIA role=alert or Live Regions to Identify Errors ARIA20: Using the region role to identify a region of the page ARIA21: Using Aria-Invalid to Indicate An Error Field Flash Techniques (all Flash Techniques on one page) Flash Technology Notes FLASH1: Setting the name property for a non-text object FLASH2: Setting the description property for a non-text object in Flash FLASH3: Marking objects in Flash so that they can be ignored by AT FLASH4: Providing submit buttons in Flash FLASH5: Combining adjacent image and text buttons for the same resource FLASH6: Creating accessible hotspots using invisible buttons FLASH7: Using scripting to change control labels FLASH8: Adding a group name to the accessible name of a form control FLASH9: Applying captions to prerecorded synchronized media FLASH10: Indicating required form controls in Flash FLASH11: Providing a longer text description of an object FLASH12: Providing client-side validation and adding error text via the accessible description FLASH13: Using HTML language attributes to specify language in Flash content FLASH14: Using redundant keyboard and mouse event handlers in Flash FLASH15: Using the tabIndex property to specify a logical reading order and a logical tab order in Flash FLASH16: Making actions keyboard accessible by using the click event on standard components FLASH17: Providing keyboard access to a Flash object and avoiding a keyboard trap FLASH18: Providing a control to turn off sounds that play automatically in Flash FLASH19: Providing a script that warns the user a time limit is about to expire and provides a way to extend it FLASH20: Reskinning Flash components to provide highly visible focus indication FLASH21: Using the DataGrid component to associate column headers with cells FLASH22: Adding keyboard-accessible actions to static elements FLASH23: Adding summary information to a DataGrid FLASH24: Allowing the user to extend the default time limit FLASH25: Labeling a form control by setting its accessible name FLASH26: Applying audio descriptions to Flash video FLASH27: Providing button labels that describe the purpose of a button FLASH28: Providing text alternatives for ASCII art, emoticons, and leetspeak in Flash FLASH29: Setting the label property for form components FLASH30: Specifying accessible names for image buttons FLASH31: Specifying caption text for a DataGrid FLASH32: Using auto labeling to associate text labels with form controls FLASH33: Using relative values for Flash object dimensions FLASH34: Turning off sounds that play automatically when an assistive technology is detected FLASH35: Using script to scroll Flash content, and providing a mechanism to pause it FLASH36: Using scripts to control blinking and stop it in five seconds or less Silverlight Techniques (all Silverlight Techniques on one page) Silverlight Technology Notes SL1: Accessing Alternate Audio Tracks in Silverlight Media SL2: Changing The Visual Focus Indicator in Silverlight SL3: Controlling Silverlight MediaElement Audio Volume SL4: Declaring Discrete Silverlight Objects to Specify Language Parts in the HTML DOM SL5: Defining a Focusable Image Class for Silverlight SL6: Defining a UI Automation Peer for a Custom Silverlight Control SL7: Designing a Focused Visual State for Custom Silverlight Controls SL8: Displaying HelpText in Silverlight User Interfaces SL9: Handling Key Events to Enable Keyboard Functionality in Silverlight SL10: Implementing a Submit-Form Pattern in Silverlight SL11: Pausing or Stopping A Decorative Silverlight Animation SL12: Pausing, Stopping, or Playing Media in Silverlight MediaElements SL13: Providing A Style Switcher To Switch To High Contrast SL14: Providing Custom Control Key Handling for Keyboard Functionality in Silverlight SL15: Providing Keyboard Shortcuts that Work Across the Entire Silverlight Application SL16: Providing Script-Embedded Text Captions for MediaElement Content SL17: Providing Static Alternative Content for Silverlight Media Playing in a MediaElement SL18: Providing Text Equivalent for Nontext Silverlight Controls With AutomationProperties.Name SL19: Providing User Instructions With AutomationProperties.HelpText in Silverlight SL20: Relying on Silverlight AutomationPeer Behavior to Set AutomationProperties.Name SL21: Replacing A Silverlight Timed Animation With a Nonanimated Element SL22: Supporting Browser Zoom in Silverlight SL23: Using A Style Switcher to Increase Font Size of Silverlight Text Elements SL24: Using AutoPlay to Keep Silverlight Media from Playing Automatically SL25: Using Controls and Programmatic Focus to Bypass Blocks of Content in Silverlight SL26: Using LabeledBy to Associate Labels and Targets in Silverlight SL27: Using Language/Culture Properties as Exposed by Silverlight Applications and Assistive Technologies SL28: Using Separate Text-Format Text Captions for MediaElement Content SL29: Using Silverlight "List" Controls to Define Blocks that can be Bypassed SL30: Using Silverlight Control Compositing and AutomationProperties.Name SL31: Using Silverlight Font Properties to Control Text Presentation SL32: Using Silverlight Text Elements for Appropriate Accessibility Role SL33: Using Well-Formed XAML to Define a Silverlight User Interface SL34: Using the Silverlight Default Tab Sequence and Altering Tab Sequences With Properties SL35: Using the Validation and ValidationSummary APIs to Implement Client Side Forms Validation in Silverlight PDF Techniques (all PDF Techniques on one page) PDF Technology Notes PDF1: Applying text alternatives to images with the Alt entry in PDF documents PDF2: Creating bookmarks in PDF documents PDF3: Ensuring correct tab and reading order in PDF documents PDF4: Hiding decorative images with the Artifact tag in PDF documents PDF5: Indicating required form controls in PDF forms PDF6: Using table elements for table markup in PDF Documents PDF7: Performing OCR on a scanned PDF document to provide actual text PDF8: Providing definitions for abbreviations via an E entry for a structure element PDF9: Providing headings by marking content with heading tags in PDF documents PDF10: Providing labels for interactive form controls in PDF documents PDF11: Providing links and link text using the Link annotation and the /Link structure element in PDF documents PDF12: Providing name, role, value information for form fields in PDF documents PDF13: Providing replacement text using the /Alt entry for links in PDF documents PDF14: Providing running headers and footers in PDF documents PDF15: Providing submit buttons with the submit-form action in PDF forms PDF16: Setting the default language using the /Lang entry in the document catalog of a PDF document PDF17: Specifying consistent page numbering for PDF documents PDF18: Specifying the document title using the Title entry in the document information dictionary of a PDF document PDF19: Specifying the language for a passage or phrase with the Lang entry in PDF documents PDF20: Using Adobe Acrobat Pro's Table Editor to repair mistagged tables PDF21: Using List tags for lists in PDF documents PDF22: Indicating when user input falls outside the required format or values in PDF forms PDF23: Providing interactive form controls in PDF documents Common Failures (all Common Failures on one page) F1: Failure of Success Criterion 1.3.2 due to changing the meaning of content by positioning information with CSS F2: Failure of Success Criterion 1.3.1 due to using changes in text presentation to convey information without using the appropriate markup or text F3: Failure of Success Criterion 1.1.1 due to using CSS to include images that convey important information F4: Failure of Success Criterion 2.2.2 due to using text-decoration:blink without a mechanism to stop it in less than five seconds F7: Failure of Success Criterion 2.2.2 due to an object or applet, such as Java or Flash, that has blinking content without a mechanism to pause the content that blinks for more than five seconds F8: Failure of Success Criterion 1.2.2 due to captions omitting some dialogue or important sound effects F9: Failure of Success Criterion 3.2.5 due to changing the context when the user removes focus from a form element F10: Failure of Success Criterion 2.1.2 and Conformance Requirement 5 due to combining multiple content formats in a way that traps users inside one format type F12: Failure of Success Criterion 2.2.5 due to having a session time limit without a mechanism for saving user's input and re-establishing that information upon re-authentication F13: Failure of Success Criterion 1.1.1 and 1.4.1 due to having a text alternative that does not include information that is conveyed by color differences in the image F14: Failure of Success Criterion 1.3.3 due to identifying content only by its shape or location F15: Failure of Success Criterion 4.1.2 due to implementing custom controls that do not use an accessibility API for the technology, or do so incompletely F16: Failure of Success Criterion 2.2.2 due to including scrolling content where movement is not essential to the activity without also including a mechanism to pause and restart the content F19: Failure of Conformance Requirement 1 due to not providing a method for the user to find the alternative conforming version of a non-conforming Web page F20: Failure of Success Criterion 1.1.1 and 4.1.2 due to not updating text alternatives when changes to non-text content occur F22: Failure of Success Criterion 3.2.5 due to opening windows that are not requested by the user F23: Failure of 1.4.2 due to playing a sound longer than 3 seconds where there is no mechanism to turn it off F24: Failure of Success Criterion 1.4.3, 1.4.6 and 1.4.8 due to specifying foreground colors without specifying background colors or vice versa F25: Failure of Success Criterion 2.4.2 due to the title of a Web page not identifying the contents F26: Failure of Success Criterion 1.3.3 due to using a graphical symbol alone to convey information F30: Failure of Success Criterion 1.1.1 and 1.2.1 due to using text alternatives that are not alternatives (e.g., filenames or placeholder text) F31: Failure of Success Criterion 3.2.4 due to using two different labels for the same function on different Web pages within a set of Web pages F32: Failure of Success Criterion 1.3.2 due to using white space characters to control spacing within a word F33: Failure of Success Criterion 1.3.1 and 1.3.2 due to using white space characters to create multiple columns in plain text content F34: Failure of Success Criterion 1.3.1 and 1.3.2 due to using white space characters to format tables in plain text content F36: Failure of Success Criterion 3.2.2 due to automatically submitting a form and presenting new content without prior warning when the last field in the form is given a value F37: Failure of Success Criterion 3.2.2 due to launching a new window without prior warning when the selection of a radio button, check box or select list is changed F38: Failure of Success Criterion 1.1.1 due to not marking up decorative images in HTML in a way that allows assistive technology to ignore them F39: Failure of Success Criterion 1.1.1 due to providing a text alternative that is not null (e.g., alt="spacer" or alt="image") for images that should be ignored by assistive technology F40: Failure of Success Criterion 2.2.1 and 2.2.4 due to using meta redirect with a time limit F41: Failure of Success Criterion 2.2.1, 2.2.4, and 3.2.5 due to using meta refresh to reload the page F42: Failure of Success Criteria 1.3.1, 2.1.1, 2.1.3, or 4.1.2 when emulating links F43: Failure of Success Criterion 1.3.1 due to using structural markup in a way that does not represent relationships in the content F44: Failure of Success Criterion 2.4.3 due to using tabindex to create a tab order that does not preserve meaning and operability F46: Failure of Success Criterion 1.3.1 due to using th elements, caption elements, or non-empty summary attributes in layout tables F47: Failure of Success Criterion 2.2.2 due to using the blink element F48: Failure of Success Criterion 1.3.1 due to using the pre element to markup tabular information F49: Failure of Success Criterion 1.3.2 due to using an HTML layout table that does not make sense when linearized F50: Failure of Success Criterion 2.2.2 due to a script that causes a blink effect without a mechanism to stop the blinking at 5 seconds or less F52: Failure of Success Criterion 3.2.1 and 3.2.5 due to opening a new window as soon as a new page is loaded F54: Failure of Success Criterion 2.1.1 due to using only pointing-device-specific event handlers (including gesture) for a function F55: Failure of Success Criteria 2.1.1, 2.4.7, and 3.2.1 due to using script to remove focus when focus is received F58: Failure of Success Criterion 2.2.1 due to using server-side techniques to automatically redirect pages after a time-out F59: Failure of Success Criterion 4.1.2 due to using script to make div or span a user interface control in HTML without providing a role for the control F60: Failure of Success Criterion 3.2.5 due to launching a new window when a user enters text into an input field F61: Failure of Success Criterion 3.2.5 due to complete change of main content through an automatic update that the user cannot disable from within the content F63: Failure of Success Criterion 2.4.4 due to providing link context only in content that is not related to the link F65: Failure of Success Criterion 1.1.1 due to omitting the alt attribute or text alternative on img elements, area elements, and input elements of type "image" F66: Failure of Success Criterion 3.2.3 due to presenting navigation links in a different relative order on different pages F67: Failure of Success Criterion 1.1.1 and 1.2.1 due to providing long descriptions for non-text content that does not serve the same purpose or does not present the same information F68: Failure of Success Criterion 4.1.2 due to a user interface control not having a programmatically determined name F69: Failure of Success Criterion 1.4.4 when resizing visually rendered text up to 200 percent causes the text, image or controls to be clipped, truncated or obscured F70: Failure of Success Criterion 4.1.1 due to incorrect use of start and end tags or attribute markup F71: Failure of Success Criterion 1.1.1 due to using text look-alikes to represent text without providing a text alternative F72: Failure of Success Criterion 1.1.1 due to using ASCII art without providing a text alternative F73: Failure of Success Criterion 1.4.1 due to creating links that are not visually evident without color vision F74: Failure of Success Criterion 1.2.2 and 1.2.8 due to not labeling a synchronized media alternative to text as an alternative F75: Failure of Success Criterion 1.2.2 by providing synchronized media without captions when the synchronized media presents more information than is presented on the page F77: Failure of Success Criterion 4.1.1 due to duplicate values of type ID F78: Failure of Success Criterion 2.4.7 due to styling element outlines and borders in a way that removes or renders non-visible the visual focus indicator F79: Failure of Success Criterion 4.1.2 due to the focus state of a user interface component not being programmatically determinable or no notification of change of focus state available F80: Failure of Success Criterion 1.4.4 when text-based form controls do not resize when visually rendered text is resized up to 200% F81: Failure of Success Criterion 1.4.1 due to identifying required or error fields using color differences only F82: Failure of Success Criterion 3.3.2 by visually formatting a set of phone number fields but not including a text label F83: Failure of Success Criterion 1.4.3 and 1.4.6 due to using background images that do not provide sufficient contrast with foreground text (or images of text) F84: Failure of Success Criterion 2.4.9 due to using a non-specific link such as "click here" or "more" without a mechanism to change the link text to specific text. F85: Failure of Success Criterion 2.4.3 due to using dialogs or menus that are not adjacent to their trigger control in the sequential navigation order F86: Failure of Success Criterion 4.1.2 due to not providing names for each part of a multi-part form field, such as a US telephone number F87: Failure of Success Criterion 1.3.1 due to inserting non-decorative content by using :before and :after pseudo-elements and the 'content' property in CSS F88: Failure of Success Criterion 1.4.8 due to using text that is justified (aligned to both the left and the right margins) F89: Failure of Success Criteria 2.4.4, 2.4.9 and 4.1.2 due to not providing an accessible name for an image which is the only content in a link F90: Failure of Success Criterion 1.3.1 for incorrectly associating table headers and content via the headers and id attributes F91: Failure of Success Criterion 1.3.1 for not correctly marking up table headers F92: Failure of Success Criterion 1.3.1 due to the use of role presentation on content which conveys semantic information F93: Failure of Success Criterion 1.4.2 for absence of a way to pause or stop an HTML5 media element that autoplays Appendix A: Acknowledgements Appendix B: References Top Contents Intro Next: Technique G1