WCAG 2 Restructuring Proposal [DRAFT] - RELEASE 2
NOTES ON THIS DRAFT --
This draft represents a proposed redraft of the central core of WCAG 2.0.
This is NOT the WCAG guidelines but a proposal to the group for its
consideration. If it looks good we can use this as a base to move forward
and edit it into what we want. If not we can return to the current draft and
work off of it.
The proposal attempts to address as many of the open issues and to
incorporate the consensus items or decisions reached as well as to address a
number of different issues uncovered in the process.
It reorganizes the checkpoints into 5 guidelines to provide a clearer
organization and to address some key open issues or quandaries.
The result is
- two guidelines (ensuring perceivability and operability) that deal with
topics that are more binary in nature (the content either is or it
isn't);
- two guidelines (facilitating orientation/navigation and facilitating
comprehension) that are more continuous in nature (there are many things
that can be done and you usually don't have a clear point where you can
say you are finished and more cannot be done).
- and a fifth one (crosslists cross cutting issues that would apply
across the areas.
It is also interesting to note that:
- guidelines 1 and 2 have more to do with what you do with the content to
make it accessible -- and could be done by a web page designer/coder
while
- guidelines 3 and 4 also involve the content and would involve the
author or change what the author wrote.
As we have author-artisits that 'write' with media and involve themselves
in all aspects, we may find that authors want to assert themselves more in
all four.
The last category is items that would impact all four of the first
guidelines so have not quite figured out how to handle them except to have
them in separate category.
The fifth group is also less worked on than 1 through 4 because the group
is still wrestling with it.
Table of Contents
Essential to any access to Web content is the ability of the user to be
able to perceive the content.
Checkpoint 1.1 Provide a text equivalent for
all aspects of non-text content that can be expressed in words.
Success Criteria
You will have successfully provided a text equivalent for all aspects of
non-text content that can be expressed in words if:
- Non-text content that can be expressed in words has a text-equivalent
explicitly associated with it that fulfills the same function as the
non-text content (i.e. to present information and/or to label an
action).
- Non-text content that can not be expressed in words has a descriptive
label provided as it's text-equivalent
Definitions (informative)
A text equivalent
- serves the same function as the non-text content.
- communicates the same information as the non-text content.
- may contain structured content or metadata.
- can be easily converted to Braille or speech, or displayed in a larger
font or different colors.
Non-text content includes but is not limited to images, text in raster
images, image map regions, animations (e.g., animated GIFs), applets and
programmatic objects, ASCII art, scripts that present content, images used as
list bullets, spacers, graphical buttons, sounds (played with or without user
interaction), stand-alone audio files, audio tracks of video, and video.
Benefits (informative)
Individuals who are blind, have low vision, have cognitive disabilities or
have trouble reading text for any reason can have the text read aloud to
them. Individuals who are deaf, are hard of hearing or who are having trouble
understanding the audio information for any reason can read the text
presentation or have it translated and presented as sign language.
Individuals who are blind or deaf-blind can have the information presented in
Braille.
Examples (informative)
- Example 1: a short label.
A right arrow icon is used to link to the next slide in a sideshow. The
text equivalent is "Next."
- Example 2: a short label and a longer explanation of a data chart.
A bar chart compares how many widgets were sold in June, July, and
August. The short label says, "Graph of the numbers of widgets sold in
June, July, and August." The longer explanation provides the data
presented in the chart.
- Example 3: a short label and a longer explanation of animation.
An animation shows how to tie a knot. The short label says, "An animation
showing how to tie a square knot." The longer explanation describes the
hand movements needed to tie the knot.
- Example 4: a short label and a transcript for an audio file that can be
described in words.
An audio file is embedded in a Web page. The short label says, "Chairman
Mao's speech to the assembly, 1953" A link to a text transcript is
provided immediately after the clip.
- Example 5: a label for content that cannot be described in words.
An audio file is embedded in a Web page. The short label says,
"Beethoven's 5th Symphony performed by the Chicago Symphony
Orchestra."
Checkpoint 1.2 Provide
synchronized media equivalents for time-dependent presentations.
Success criteria
You will have successfully provided synchronized media equivalents for
time-dependent presentations if:
- an audio description of all significant visual
information in scenes, actions and events is provided to the extent
possible given the constraints posed by the existing audio track and
constraints on freezing the image to insert additional auditory
description.
- all significant dialogue and sounds are captioned.
- descriptions and captions are synchronized with
the events they represent.
- If web content is a real-time broadcast, and
synchronized media equivalents are available, they are provide
[Issue: this set does not yet require provision of
media-equivalents for live broadcast. The reason is that it is not clear how
to handle problems with webcams, etc. If someone points a webcam out the
window, or at the coffeee pot -- do they need to hire someone to provide a
running commentarey? We should discuss and decide to require or not. UNDER
WHAT CIRCUMSTANCES WOULD WE REQUIRE EQUIVALENTS == AND WHEN WOULD WE NOT -
AND STILL ALLOW COMPLIANCE WITH THIS CHECKPOINT]
Definitions (informative)
A time-dependent presentation is a presentation which
- is composed of synchronized audio and visual tracks (e.g., a movie),
OR
- a presentation which requires the user to respond interactively at
specific times in the presentation.
Media equivalents present essential audio
information visually (captions) and essential video information
auditorily (audio descriptions).
- captions are text equivalents of auditory
information from speech, sound effects, and ambient sounds that are
synchronized with the multimedia presentation.
- audio descriptions are
equivalents of visual information from actions, body language, graphics,
and scene changes that are voiced (either by a human or a speech
synthesizer) and synchronized with the multimedia presentation.
Benefits (informative)
People who are deaf or have a hearing loss can access the auditory
information through the captions. People who are blind or have low vision as
well as those with cognitive disabilities who have difficulty interpreting
visually what is happening benefit from the audio descriptions of the visual
information.
People without disabilities also benefit from the media equivalents.
People in noisy environments or with muted sound often use captions. Captions
are used by many to develop language and reading skills. Audio descriptions
also provide visual information for people who are temporarily looking away
from the video presentation such as when following an instructional video and
looking at their hands. Captions and text descriptions can also be used to
index and search media files.
Note:Time-dependant presentations that require
dual, simultaneous attention with a single sense can present significant
barriers to some users. Depending on the nature of the of presentation, it
may be possible to avoid scenarios where, for example, a deaf user would be
required to watch an action on the screen and read the captions at the same
time. However, this would not be achievable for live broadcasts (ex. a
football game). Where possible, provide content so that it does not require
dual, simultaneous attention or so that it gives the user the ability to
effectively control/pause different media signals.
Examples (informative)
- Example 1: a movie clip with audio description and
captions.
A clip from a movie is published on a Web site. In the clip, a child is
trying to lure an alien to the child's bedroom by laying a trail of
candy. The child mumbles inaudibly to himself as he lays the trail. When
not watching the video, it is not obvious that he is laying a trail of
candy since all you hear is the mumbling. The audio description that is
interspersed with the child's mumbling says "Charlie lays a piece of
candy on each stair leading to his room." The caption that appears as he
mumbles is, "[inaudible mumbling]."
- Example 2: a video clip of a news story.
A video clip accompanies a news story about the recent flooding in a
major city. The reporter describes what is seen, for everyone. No audio
description is necessary. The captions display what the reporter is
saying.
- Example 3: a silent animation.
An animation shows a clown slipping on a banana and falling down. There
is no audio track for this animation. No captions or audio description
are required. Instead, provide a text equivalent as described in
checkpoint 1.1.
Checkpoint 1.3 [1.5] Make all content and structure
available independently of presentation.
Success criteria
You will have successfully made content and structure available
independent of presentation if
- Any information that is conveyed through presentation formatting is
also provided in either text or structure.
- Any structure in the content is exposed through markup or data
model.
- The following can be derived programmatically (e.g. through markup or
data model) from the content without interpreting presentation.
- at least one logical, linear reading order
- any hierarchical elements, such as headings, paragraphs and
lists
- any relationships between elements, such as cross-references and
associations between labels and controls
- any emphasis
[Issue: will people know how to determine if a logical reading order
can be derived - or how to do it to test
3a]
Definitions (informative)
Content is the information or
meaning and function.
Presentation is the rendering of
the content and structure in a form that can be sensed by the user.
Structure includes both
hierarchical structure of the content and nonhierarchical relationships such
as cross-references, or the correspondence between header and data cells in a
table.
Benefits (informative)
Content and presentation can be separated because the rules that control
how content is displayed can be separated from the markup that denotes the
structure of the content. For example, content that separates content and
structure from presentation makes it possible for a user to change the
presentation to meet his/her needs, by configuring his UAAG-compliant user
agent.
Typically, style rules are stored separately from the content to which
they apply, in resources known as style sheets. To facilitate the
presentation of Web content by a range of devices (high and low-resolution
displays, printers, speech devices, etc.), it is advisable to associate a
variety of style sheets with your Web content.
Examples (informative)
- Example 1: a multi-column document.
A document is marked up with headings, paragraphs and other structural
features. It is presented visually in three columns. The markup that
creates the columns is separate from the markup that specifies the
logical structure of the document.
- Example 2: a scrolling list of stock prices.
Current stock quotes are scrolled horizontally across the screen. The
data is separate from the methods used to scroll the text across the page.
Also essential to access is the ability to be able to operate the
interface elements on the page.
Checkpoint 2.1 [2.5] Provide keyboard access to all
functionality of the content.
Success criteria
You will have successfully keyboard access to all functionality of the
content if:
- all functions of the content can be operated from a standard keyboard
without requiring simultaneous activation of multiple character keys.
Benefits (informative)
Individuals who are blind (and cannot use pointing devices) can have
access to the functionality of the product.
Individuals with severe physical disabilities can use speech input
(coupled with a keyboard emulator which injects the spoken text or commands
as if they were typed on the keyboard) to enter data or control the
device.
Examples (informative)
Example 1: a submit button. A submit button may be activated by clicking
on it with the mouse, tabbing to it with the keyboard then pressing the Enter
key, selecting it through voice input, or pressing it with a stylus.
Checkpoint 2.2 [2.4] Allow users to control any time
limits on their interaction or responses unless control is not possible due
to nature of real-time events or competition.
Success criteria
You will have successfully either given users control over how long they
can interact with content that requires a timed response or given them as
much time as possible if:
- the user is allowed to deactivate time-out,
- or the user is allowed to adjust the time-out over a wide range which
is at least 10 times the average user's preference,
- or the user is warned before time expires and given at least 10 seconds
to extend the time available to them,
- or the time-out is due to a real-time event (e.g. auction) and no
alternative to the time-out is possible
- or the time limit is part of a competitive activity where timing is an
essential part of the activity (e.g. competitive gaming, time based
testing).
Real-time events
Competitive activity: an activity where timing is an essential part of the
design of the activity. Removal of the time element would change the
performance of the participants. None time based activities might be
preferred and may be required for some venues but this would require a
complete redesign of the activity or test and would therefore fall under
guidelines
People with reading disabilities, cognitive disabilities, and learning
disabilities often need longer than most people to read and comprehend
written text. People with physical disabilities might not be able to move
quickly or accurately enough to interact with moving objects.
Content that is updated often might not be processed and read in time or
in the proper order by an assistive technology or voice browser.
Examples of content that requires a response within a timed
interval:
- automatic refresh,
- redirection,
- blinking or scrolling text
- dialog that disappears after a short period.
- shutdown or deactivation of pager if activity is not received in XX
time
Examples of application of checkpoint
- Example 1: blinking text:
Client-side scripting is used to create blinking text. The user can
deactivate the use of scripting in his or her browser or override the use
of scripts with a user style sheet.
- Example 2: a news site that is updated regularly.
A new site causes its front page to be updated every 1/2 hour. The front
page contains minimal text and primarily consists of links to content. A
user who does not wish the page to update selects a checkbox. The
checkbox is in the "user preferences" portion of the site which is one of
the first links on each page.
Checkpoint 2.3 [2.6] Avoid causing the screen to
flicker.
Success criteria
You will have successfully avoided screen flicker if:
- animation or other content does not visibly or purposely flicker
between 3 and 49 Hz.
- if flicker is unavoidable - user is warned of the flicker before they
go to the page , and a version of the content without flicker is
provided.
Benefits (informative)
People with photosensitive epilepsy can have seizures triggered by
flickering or flashing in the 3 to 49 flashes per second (Hertz) range with a
peak sensitivity at 20 flashes per second as well as quick changes from dark
to light (like strobe lights).
People with distractibility problems may not be able to focus on page
content with flicker occurring in same visual field.
Key to effective use of web content is the ability to keep one's
orientation within a document and/or website, and the ability to efficiently
move about in the site or document.
Checkpoint 3.1 [1.3A] Provide structure within
content.
Success criteria
- Author(s) or others have reviewed content and added as much structure
as they felt was possible and appropriate.
- The following minimum structure elements are present
NOTE: Because the form and origin (including letters,
art, historical documents, etc.) of content varies so greatly, specific
criteria for the amount of structure to be put into content can not be
standardized. Objective success criteria cannot therefore be formulated that
would apply across media and documents.
Advisory recommendations are however listed below to provide guidance in
adding key structural elements into the content. See also the techniques
documents for the different technologies.
Advisory Recommendations to Consider (informative)
- Break up text into logical paragraphs.
- Provide hierarchical sections and titles, particularly for longer
documents
- Provide a table of contents or other navigation map
- Reveal important nonhierarchical relationships, such as
cross-references, or the correspondence between header and data cells in
a table, so that they are represented unambiguously in the markup or data
model.
- Provide a search function within the document if it spans multiple
documents.
- Provide a mechanism for obtaining a copy of the document in a single
file.
- Divide very large works into sections and or chapters with logical
labels.
[Issue: Are there others that should included in list]
Note: some forms of communication such as personal
letters and poetry do not lend themselves to hierarchical division or headers
within a document.
Definitions (informative)
The structure of content represents changes in
context. For example,
- A book is divided into chapters, paragraphs, lists, etc. Chapter titles
help the reader anticipate the meaning of the following paragraphs. Lists
clearly indicate separate, yet related ideas. An italicized phrase
emphasizes an important idea. All of these divisions help the reader
anticipate changes in context.
- A bicycle is divided into wheels and a frame. Further, a wheel is
divided into a tire and a rim. In an image of the bicycle, one group of
circles and lines becomes "wheel" while another group becomes
"frame."
Issue: does the definition distinguish adequately
between presentation (e.g., italics) and the corresponding structure (e.g.,
emphasis), or is the present wording likely to confuse readers?
Issue: Provide an adequate definition of "data model" to
cover such phenomena as PDF logical structure, XML information sets that are
not represented in markup, etc.
When the logical structure is provided in markup or a data model,
- Users with physical disabilities can use structure to more easily jump
between paragraphs, chapters, sections etc.
- Users with cognitive disabilities can use structure (chapter titles,
headers, etc.) to provide more context for the text that follows them.
They also provide warning of a change in context and reorient the user to
the new focus.
- Users with blindness or low vision can jump from header to header to
get an overview or to more quickly "skim" to the section they are
interested in.
- Readers with low vision can sometimes (depending on display technology)
change how chapter titles and headers are displayed to make them more
visible -and easier to use when skimming the document.
- the content can be presented on a variety of devices because the device
software can choose only those elements of the content that it is able to
display and display them in the most effective way for that device.
- Example 1: a physics dissertation.
A dissertation contains well-defined sections such as "Abstract," "Table
of Contents," "Chapter 1," etc. The pieces in each section (paragraphs,
subheadings, quotes) are denoted with structural markup.
- Example 2: a scalable image of a bike.
Lines and a circle (spokes and rim) are grouped into a "wheel." Lines in
a triangle that attach to each wheel are grouped into a "frame."
- Example 3: user interface.
User interface controls are divided into organized groups.
Checkpoint 3.2 [3.2] Emphasize structure through
presentation(s), positioning, and labels.
Success criteria
- Author(s) or others have reviewed content and emphasized structure as
they felt was possible and appropriate.
- The following minimum structural emphases are present.
NOTE: Because the form and origin (including letters,
art, historical documents, etc) of content varies so greatly, specific
criteria for the amount of structure to be put into content can not be
standardized. Objective success criteria cannot therefore be formulated that
would apply across media and documents.
Advisory recommendations are however listed below to provide guidance in
emphasizing the structure of content. See also the techniques documents for
the different technologies.
Advisory Recommendations to Consider (informative)
- For visual presentations, use font variations, styles, size and white
space to emphasize structure.
- Use color and graphics to emphasize structure.
- For auditory presentations, use different voice characteristics
and/sounds for major headings, sections and other structural
elements.
- If content is targeted for a specific user group and the presentation
of the structured content is not salient enough to meet the needs of your
audience, use additional graphics, colors, sounds, and other aspects of
presentation to emphasize the structure.
NOTE: Ensure that the structural and semantic
distinctions are provided in the markup. Refer to checkpoint 2.2.
Benefits (informative)
Presentation that emphasizes structure:
- enables users with cognitive and visual disabilities to oriented
themselves within the content,
- enables all users to move quickly through the content and notice major
content divisions
- enables all users, but particularly users with visual or cognitive
disabilities to focus on important content,
- enables all users, but particularly users with visual or cognitive
disabilities to separate the different types of content.
Checkpoint 3.3 [2.1] Provide multiple methods to
explore site contents.
Issue: We are currently discussing the scope of this checkpoint and
what is required. Does providing multiple site navigation mechanisms increase
accessibility or are we trying to get at something else? Refer to the
benefits for the issue we are trying to tackle. How do we set limits for when
to apply this checkpoint? If a site consists of only 5 pages, a site map
might look exactly like the home page.
You will have successfully provided multiple methods for exploring site
contents if:
- more than one method (the home "page" with links is one method) is
provided for sites that are more than 2 layers (a home "page" and one
layer of "pages" linked off of it).
- the site exploration method(s) are easy to locate.
Site navigation mechanism - a mechanism for easily
orienting and moving about within the site. Site navigation mechanisms
include but are not limited to:
- Home page with hyperlinks on it and subsequent pages that will lead to
the other pages at the site.
- a site map(s)
- a search engine
- an expanding outline
- a dynamic fisheye view showing all linked pages or topics related to
any page.
- 3-d virtual representations of site content
Providing different navigation mechanisms can provide a better match
between different peoples skill, background knowledge, visual vs. text
orientation, and the type of information they are seeking at the moment.
People with cognitive disabilities may find it easier to ask for what they
want than to deduce its location from categorical choices.
People with low vision or blindness may find techniques that fetch
everything that relates to a topic of interest to be easier than techniques
that require them to scan larger lists for the items.
NOTE: Large documents should also consider including
multiple mechanisms for navigation such as a hyperlinked table of contents,
internal hyperlinks, an ability to collapse by headers, etc.
Checkpoint 3.4 [3.1] Use Consistent But Not Necessarily Identical
Presentation
Success criteria
- Author(s) or others have reviewed content and used consistent
presentation where they felt it was possible and appropriate.
NOTE: Consistency can make content easier to navigate
and to find controls or features on a page. Too much consistency can be
disorienting and make it harder to tell where one is or where information was
located.
Advisory recommendations are however listed below to provide guidance
consistent presentation. See also the techniques documents for the different
technologies.
Advisory Recommendations to Consider (informative)
- Place navigation bars in a consistent location whenever possible
- Similar layout for user interface components is used for sections or
whole site,
- Similar user interface components are labeled with similar
terminology,
- Consistent use of headers
- Use templates for consistent presentation for sections or whole
site
- Pages with similar function have similar appearance and layout
Presentation includes, but is not limited to:
- position,
- font, font size,
- color
- voice and voice characteristics
- sounds
- white space
Consistency helps users predict where to find information on each page of
your site. It also helps users determine the relationships between items in
the content. This understanding of the structure helps users navigate, orient
themselves.
Note that differences in presentation help users determine that they have
succeeded in loading a new page. Having pages which are similar but clearly
different helps with this and also helps users distinguish between
content.
Checkpoint 3.5 [2.2] Provide consistent and
predictable responses to user actions.
Success criteria
- Author(s) or others have reviewed content for consistent and
predictable responses to user actions.
- Where inconsistent or unpredictable responses are essential to the
function of the content (e.g. mystery games, adventure games, tests,
etc.) the user is warned in advance of encountering them.
- The following minimum criteria are met.
NOTE: Consistency can make content easier to navigate
and to find controls or features on a page. Too much consistency can be
disorienting and make it harder to tell where one is or where information was
located.
Advisory recommendations are however listed below to provide guidance
consistent presentation. See also the techniques documents for the different
technologies.
- controls that look or sound the same are designed to act the same,
- conventions likely to be familiar to the user have been followed,
- unusual user interface features or behaviors that are likely to confuse
the first-time user are described to the user before they encounter
them.
Providing responses to user actions is important feedback for the user.
This lets them know that your site is working properly and encourages them to
keep interacting. When the user receives an unexpected response, they might
think something is wrong or broken. Some people might get so confused they
will not be able to use your site. Common responses to user actions:
- rollover effects for mouse movements
- auditory menu order
- pop-up menus,
- form submission with enter key,
These actions should be predictable and sensible to the end user. Make
interactions consistent, both throughout the site and with commonly used
interaction metaphors used throughout the Web.
- Example 1: navigation bars.
- Example 2: frames.
- Example 3: forms.
Some of these examples are very brief. Should they be
expanded and clarified with further details?
Checkpoint 3.6 [2.3] Either give users control of
mechanisms that cause extreme changes in context or warn them of pending
changes.
You will have successfully either given users control of mechanisms that
cause extreme changes in context or warn them of pending changes if:
- Either
- an easy to find setting, that persists for the site visit, is
provided for the user to deactivate processes or features that cause
extreme changes in context
- or extreme changes in context are identified before they occur so
the user can determine if they wish to proceed or so they can be
prepared for the change
.
Mechanisms that cause extreme changes in context include:
- opening a new browser window,
- frames that do not track history making the "back" button of most
browsers useless.
Issue: do these have counterparts in non-visual
interfaces?
If the user is unable to track visual cues that make extreme changes
obvious, then they will not realize the context has changed. People who are
blind, some people with low vision, some people with dyslexia and other
people who have difficulty interpreting visual cues need guidance during
extreme changes in context.
- Example 1: a form to deactivate pop-up windows.
Provide a checkbox on a page of links to let the user select whether they
want the resultant pages to appear in new windows or not.
- Example 2: a warning given before a pop-up window.
At the end of a news story, several links are provided for more
information. At the beginning of each link is an icon of an arrow with
the text equivalent, "Link will open in new window."
Checkpoint 3.7 [2.7A] Provide methods to minimize
error and provide graceful recovery.
Issue: This is a new checkpoint that is being explored.
It does not have full support of the working group. We know that spelling
mistakes are a serious issue for people with writing disabilities and
dyslexia. We have generalized this checkpoint to include all input errors but
highlight spelling mistakes. Are there other input errors we should
highlight? Are there other ideas we can list?
Success criteria
- Author(s) or others have reviewed content and incorporated error
prevention and recovery methods they felt were possible and
appropriate.
- The following minimum structural emphases are present.
NOTE: Because some authors do not have control of the
server side services or do not know how to program such services, and the
user client may not support scripting or it may be turned off, it is not
possible to require specific types of error checking and recovery.
Advisory recommendations are however listed below to provide guidance in
graceful error recovery. See also the techniques documents for the different
technologies.
- the error is identified to the user
- correct options are provided as cues to the user
- actions are reversible
- where not reversible action is checked for errors in advance.
- where not reversible and not checkable a confirmation is asked before
acceptance
- checks for misspelled words are applied and correct spellings are
suggested when text entry is required,
- where possible, the user is allowed to select from a list of options
rather than generate text.
People with writing disabilities and people with dyslexia often have
difficulty writing text in forms or other places that need text input. People
with speech disabilities might not be recognized properly in voice input
applications.
- Example 1: a search engine.
A search engine is provided with a variety of search options for
different skill levels and preferences. It includes a spell checker and
offers "best guess" alternatives, query-by-example searches, and
similarity searches.
Guideline 4 - Comprehension. Make it as easy
as possible to understand the content and controls.
We each gain knowledge in different ways. Some people read something and
understand, others have to experience it, while others need only to see
something. To help people understand the information you are presenting,
consider the various ways that people learn. Keep in mind the variety of
backgrounds and experiences people will bring to your site. Using language,
illustrations, and concepts that they are likely to know, highlighting the
differences and similarities between concepts, and providing explanations for
unusual terms can all facilitate understanding. .
Checkpoint 4.1 [3.3] Write as clearly and simply as is
appropriate for the content.
Success criteria
- Site owners have reviewed the materials on the site and have tried to
have the content under their control written as clearly and simply as
they feel is appropriate.
NOTE: It is very difficult to determine what makes
writing clear and simple for all topics. Some content is derived from other
sources and is copyrighted so it cannot be altered. Some materials or topics
cannot be communicated accurately in simple language. Also, since some people
cannot understand the content no matter how simply it is written, it is not
possible to make any content accessible to everyone. Specific objective
criteria that could be applied across all types of content are therefore not
possible.
Advisory recommendations are however listed below to provide guidance in
this area. See also the techniques documents for the different
technologies.
Advisory Recommendations to Consider (informative)
- Provide an outline or a summary for your document.
- Break up long paragraphs into shorter ones, with one idea per
paragraph.
- Break up long sentences into shorter ones.
- Provide accurate unique page titles.
- Ensure that headings and link text are unique and that they make sense
when read out of context.
- Provide definitions for any jargon or specialized terminology used in
your document.
- Provide explanations of figurative, metaphorical, or idiomatic uses of
language (for example, 'haven't seen you in a coons age' or 'the sight
tore my heart out')."
- Language is used that your intended audience ought to be familiar
with,
- When introducing new concepts or terms, they are defined or annotated
in language that the audience should be familiar with or definitions or
explanations are linked to that might be easier to understand.
Authors should strive for clear and simple writing to aid all users,
especially those with cognitive, learning, and/or reading disabilities. This
should not discourage you from expressing complex or technical ideas. Using
clear and simple language also benefits people whose first language differs
from your own, including those people who communicate primarily in sign
language.
Checkpoint 4.2 [3.4] Supplement text with non-text
content.
Success criteria
- Text has been supplemented with non-text content to the extent deemed
appropriate by the author.
NOTE: Supplementing text with non-text (e.g. graphics,
sound, smell, etc) is useful for all users. However there are no clear
guidelines as it relates to disability. Specific objective criteria that
could be applied across all types of content are therefore not possible.
Advisory recommendations are however listed below to provide guidance in
this area. See also the techniques documents for the different
technologies.
Advisory Recommendations to Consider (informative)
Non-text content - includes images, text in raster images, image
map regions, animations (e.g., animated GIFs), applets and programmatic
objects, ASCII art, scripts, images used as list bullets, spacers, graphical
buttons, sounds (played with or without user interaction), stand-alone audio
files, audio tracks of video, and video. Is this definition
adequate?
Sounds, graphics, videos and animations can help make concepts presented
in a Web site easier to understand, especially for people with cognitive,
reading, or learning disabilities or those who are unfamiliar with the
language of the text of the site.
Note: "Designers need to be cautious in deciding when to use
illustrations. Reading a picture is probably a learned activity that is
easier for some than others. Some users skip the pictures; others read
only the pictures. Designers must also recognize that visual
conventions are not universal and that individuals develop their own mental
schema and expectations in interpreting visual information.
For a detailed discussion of guidelines pertaining to illustrations,
consult Tufte (1983) and MacDonald-Ross (1977)." Robert W. Bailey, Ph.D.,
Human Performance Engineering, 3rd edition.] pg 431.
- Example 1: a description of a process.
A page describes how to learn to snowboard. Each step in learning how to
turn on the snowboard is illustrated with a photograph of a person doing
what is described in the text.
- Example 2: a concrete concept.
The primary concept on a page is concrete. It is discussing Mt. St.
Helens. It includes both a description of the 1981 eruption as well as
photos of the eruption and the aftermath. It links to another site that
contains video and another site that contains a 3D simulation of what
happened underneath the crust and within the volcano during the
eruption.
- Example 3: child's report of school trip.
A child went with her school on a trip to a soda pop bottling plant. She
wrote a report for her family and friends to post to the Web. In the
report, she includes the company logo as well as a picture of a soda pop
bottle, which has a unique shape. She links to the company Web site for
more information. She includes photos she took of the plant.
- Example 4: stock trading data.
A news site is comparing the performance of the economy from 3rd quarter
of this year with 3rd quarter from the last 3 years. They compare prices
of the most popular stocks. They present the data in a bar graph with a
link to the raw data they used to create the bar graph.
- Example 5: history of Jazz.
A grandfather's hobby is listening and playing to Jazz. He creates a Web
site discussing the major players from the 1940's and the styles they
were creating. When describing key pieces of work, he links to a short
sound clip from each song.
Checkpoint 4.3 [3.5] Annotate complex, abbreviated, or
unfamiliar information with summaries and definitions.
Success criteria
- Authors or site owners have reviewed the content provided annotations
for information where they feel is appropriate.
NOTE: Advisory recommendations are listed below to
provide guidance in this area. See also the techniques documents for the
different technologies.
Advisory Recommendations to Consider (informative)
- Provide a definition (with the first occurance) of phrases, words,
acronyms, and abbreviations specific to a particular community.
- Provide a summary for relationships that may not be obvious from
analyzing the structure of the table but that may be apparent in a visual
rendering of the table.
If the
presentation of the information is intended to highlight trends or
relationships between concepts, these should be explicitly stated in the
summary.
Examples of complex information:
- data tables,
- concepts that are esoteric or difficult to understand,
- content that involves several layers.
Content might be unfamiliar if you are using terms specific to a
particular community. For example, many of the terms used in this document
are specific to the disability community.
Summarizing information that is difficult to understand helps people who
do not read well. Providing a summary of the visual cues that show
relationships between complex information helps people who do not use visual
cues or who have difficulty using visual cues. For example, people who are
blind do not use any visual cues, while people with dyslexia or people with
low vision might have difficulty interpreting visual cues.
Defining key terms and specialized language will help people who are not
familiar with the topic. Providing the expansion of abbreviations and
acronyms not only helps people who are not familiar with the abbreviation or
acronym but can clarify which meaning of an abbreviation or acronym is
appropriate to use. For example, the acronym "ADA" stands for both the
American with Disabilities Act as well as the American Dental Association.
Checkpoint 4.4 [1.4] Identify the primary natural
language and and all changes in natural language.
You will have successfully identified the primary natural language of text
and text equivalents and all changes in natural language if:
- changes in language are identified at the level the changes occur.
Note: If there is never a change throughout a whole site, then
identification can occur at the highest level (usually at a page or
document level). If changes occur at the word or phrase level, then
changes should be identified at the word or phrase level using the markup
appropriate to the markup language in use.
Natural languages are those used by humans to communicate,
including spoken, written, and signed languages.
Oftentimes, phrases from various languages are interspersed in writing.
When these phrases are identified, a speech synthesizer can voice text with
the appropriate accent and pronunciation. When they are not identified, the
speech synthesizer will use the default accent and pronunciation dictionary
which can make the phrase intelligible. Identifying changes in language will
also allow a tool to ask for automatic translations of that content. When
editing content, authoring tools can switch between appropriate spelling
dictionaries.
- Example 1: a French phrase in an English sentence.
In the following sentence, "And with a certain je ne sais quoi,
she entered both the room, and his life, forever." the French phrase
"je ne sais quoi" is marked as French. Depending on the markup
language, English may either be marked as the language for the entire
document except where specified, or marked at the paragraph level.
Guideline 5 - Interoperability. Design content to
maximize compatibility with different presentation, operation and
interpretation technologies.
Checkpoint 5.1 [4.2] Use technologies according to
specification.
You will have successfully used technologies according to specification
if:
- for markup: the markup has passed validity tests of the language
(whether it be conforming to a schema, DTD, or other tests described in
the specification), structural elements and attributes are used as
defined in the specification, accessibility features are used, and
deprecated features are avoided. Issue: should there be
a qualification or exception for backward-compatibility? If so, under
what circumstances should it apply? Alternatively, if an implementor
decides to use invalid markup for backward-compatibility reasons,
shouldn't they be "honest" and indicate that they haven't satisfied this
checkpoint?
- for API's: programming standards for the language are followed and
accessibility API's are used when available.
Are protocols relevant to this checkpoint? If so, why,
and should we require that they be used according to specification? Obviously
there are interoperability advantages in doing so, but is this pertinent to
accessibility?
When languages, API's, and protocols are used according to specification,
tools that use the results will be able to do so as intended and expected.
Checkpoint 5.2 [4.4] Ensure that content remains
usable when technologies that modify default user agent processing or
behavior are turned off or not supported.
Issue: define "default" for purposes of this checkpoint.
If "default" were taken to mean "a user agent's default rendering", then this
would defeat the purpose of the checkpoint, because (for many user agents)
the default is to apply style sheets, invoke scripts and programmatic
objects, etc.
You will have successfully ensured that content remains usable when
technologies that modify default user agent processing or behavior are turned
off or not supported if:
- for technologies that associate presentation with structure, the
content is still usable and readable by the user even if stylistic or
scripting technologies are not supported or turned off.
- Example 1: Metadata.
A scalable image of the layout of a network uses metadata to label each
piece of the network and how they connect to each other. The metadata can
be used to create a text description of the network.
- Example 2: A transformation filter.
A Web site provides a transformation filter that allows users to design
how they will interact with the layout of the content on the site - with
or without images, with or without tables, etc.
- Example 3: Human resources intranet site.
The human resources department for a large company provides multiple
versions of the same content to ensure backwards compatibility with older
browsers. The IT department is not large enough to update everyone's
browsers and assistive technologies so many people make do with older
technologies.
In determining the extent to which older technologies should be supported,
keep in mind that
- assistive hardware and software are often slow to adapt to technical
advances.
- for significant groups of users, it may not be possible to obtain the
latest software or the hardware required to operate it.
Checkpoint 5.3 [4.1A] Choose technologies that support
interoperability and compatibility.
You will have successfully chosen a technology that supports the use of
these guidelines if the technology:
- permits equivalents to be associated with or synchronized with
auditory, graphical, and multimedia content,
- allows the logical structure of the content to be defined independently
of presentation,
- supports device-independence,
- is documented in published specifications and can be implemented by
user agent and assistive technology developers,
- is supported by user agents and assistive technologies.
Issue: are these success criteria complete? If not, what
should be added or changed? Should we provide a link to the XML
guidelines?
Issue: should the checkpoint be reworked (or an
additional checkpoint inserted here) to require that content be designed, as
far as possible, so that it is amenable to automated accessibility
testing?
Markup languages, multimedia formats, software interface standards, etc.,
vary in their support of accessibility. When choosing which technologies to
use, consider how easy it is to apply these guidelines.
Checkpoint 5.4 [4.3A] Ensure that user interfaces are
accessible or provide an accessible alternative.
You will have successfully designed user interfaces compatible with
assistive technology if:
- accessibility conventions of the markup or programming language (API's
or specific markup) are used,
- any applications with custom interfaces conform to at least Level A of
UAAG 1.0. If the application cannot be made accessible, an alternative
accessible solution is provided,
- device-independent access to functionality is provided,
- the interface has been tested using a variety of assistive technologies
and preferably real people with disabilities who use assistive
technologies to determine that assistive technologies can access all
information on the page or hidden within the page.
Issue: it would be possible to comply with the
checkpoint without carrying out tests (either with users or with
assistive technologies). Conversely, it is possible to conduct tests, but
still fail to meet the checkpoint (with respect to assistive technologies
that were not tested, for example). Should this success criterion be
deleted?
Asking someone to access your Web site without their assistive technology
is like asking someone to access a building without their wheelchair.
Assistive technologies are an essential part of the lives of many people with
disabilities.
FROM CYNTHIA SHELLY -- COMMENTS ON LAST ITEMS THESE WERE NOT
INCORPORATED INTO THE DOC ABOVE BECAUSE WE MISSED THEM
POSTED HERE FOR DISCUSSION
I took a stab at re-writing several of the checkpoints under guideline
4. This is really rough, but you'll get the idea. The stuff between
the tags are
explanations that would not be in the draft.
Checkpoint 4.1 [5.3 ABOVE] Choose technologies that are designed to
support accessibilit
Success Criteria:
- A technology can be considered accessible if it
- supports device independence
- includes accessibility features
- has publicly documented interfaces for interoperability
- makes use of operating system accessibility features (either directly
or via the user agent) is supported by assistive technologies in the
natural language(s) of the content.
- is implemented in user agents and/or proxies in the natural language(s)
of the content.
Checkpoint 4.2 [5.1 ABOVE] Use technologies according to specification
Success criteria
- General: You have used the accessibility features available in your
chosen technologies
- For markup:
- the markup has passed validity tests of the language*, and
- structural elements and attributes are used as defined in the
specification
- For api's:
- programming standards for the language are followed
* passing the validity tests of the language would include conforming to
a schema, DTD, or other tests described in the specification.
Checkpoint 4.4 [5.2 ABOVE] Design for backward compatibility
<notes>
Again, this is what we say when we explain the checkpoint, so let's just
say it</notes>
Success criteria:
Your site can be considered backward compatible if
- You have determined and documented your baseline browser requirements in
metadata and/or a policy statement on your site.
- Your content is still usable when features above your baseline (for
example, scripting and stylesheets) are turned off
Informative:
1) When determining your baseline browser requirements, consider that
assistive hardware and software is often slow to adapt to technological
advances, and the availability of assistive technology varies across natural
languages. Verify that assistive technology compatible with the technologies
you choose is available in the natural language(s) of your content.
2) In some situations, there are trade-offs between this checkpoint and
checkpoints 4.1 and 4.2.
Older user agents may not be compliant to standards.
Newer technologies (or their accessibility features) may break older user
agents. In these situations, you will need to make a judgment call as to
which is more important for your audience, and adjust your baseline browser
requirements accordingly.