User Agent Accessibility Guidelines 1.0
8 July 2002
This normative section defines
what it means to conform to this document and explains how to make a valid conformance claim. The following are
important conformance concepts.
- Conformance and conformance claims differ. This document
distinguishes conformance requirements and conformance claim
requirements. The sections on
unconditional conformance and
conditional conformance explain the conformance requirements. The section
on well-formed claims explains the claim
requirements (e.g., identification of the components that make up the user
agent, the operating environment in which they run, etc.) Here is a sample claim (expressed in HTML):
<p>On 8 July
2002, UserAgent X (version 2.3) running on MyOperatingSystem (version 4.2)
conforms to <abbr title="the World Wide Web
Consortium">W3C</abbr>'s "User Agent Accessibility Guidelines 1.0",
http://www.w3.org/WAI/UA/WD-UAAG10-20020708, level Double-A. Supported
conformance labels Image, Animation, Audio, Events, and Selection. Unsupported
conformance labels: Video, Speech, Pointer, and Voice. A <a
href="http://example.com/checkpoints">list</a> of formats used to
satisfy the requirements, and of checkpoints that do not apply is available
- Modular conformance. A conforming user agent is not required to be a single
piece of software. In general, a conforming user agent will consist of several
coordinated components, such as a browser, a multimedia player, documentation
on the Web, etc. The current document places no restrictions on the type or
number of components that make up the "subject of a conformance claim", i.e., the set of
components about which someone has made a conformance claim.
- Conditional conformance. A user agent may conform to this
document without satisfying every checkpoint. This document allows "conditional conformance", which means
conformance to fewer than (or more than) a default set of requirements.
Claimants do not arbitrarily choose which requirements they wish to satisfy in
order to conform conditionally; conditional conformance is governed by rules
for adding and removing well-defined sets of requirements. Each set is
identified by a
conformance labels. These mechanisms are called:
When a user agent conforms conditionally, a conformance claim must indicate how
the set of satisfied requirements differs from the default set; see the section
on well-formed claims.
- Conformance levels,
- Content type labels,
- Events label,
- Selection label.
- Input modality labels,
- Applicability. Some checkpoints may not apply to a particular user agent because of the nature
of the user agent's user interface or the nature of the format(s) implemented
by the user agent. If a checkpoint (or portion of a checkpoint) doesn't apply,
the user agent is not required to satisfy it for conformance. A claimant must
state in a well-formed conformance claim which
checkpoints, if any, do not apply. See the section on
applicability for information about how to determine whether a checkpoint
In this document (notably in the checkpoints and in this section on
conformance), the terms "must", "should", and "may" (and related terms) are
used in accordance with RFC 2119
Note: Conformance to the requirements of this document is
expected to be a strong indicator of accessibility, but it is neither a
necessary nor sufficient condition for ensuring the accessibility of software.
Some software may not conform to this document but still be accessible to some
users with disabilities. Conversely, some software may conform to this document
but still be inaccessible to some users with disabilities. Some requirements of
this document may not benefit some users for some content, but the requirements
are expected to benefit many users with disabilities, for general purpose
content. For more information, please see the section on known limitations of this document, and the
section on restricted functionality and
A user agent conforms unconditionally to this document if:
- It satisfies the
default set of conformance requirements, defined to be all of the
requirements of all of the provisions of all the checkpoints, as well as all of
the normative inclusions and
exclusions that qualify the checkpoints, and
- It satisfies these requirements as follows:
- For each checkpoint in guideline 6, the requirements are satisfied by implementing
- For all other checkpoints, the requirements are satisfied through at least
one mechanism (e.g., user interface feature or configuration file) other than
Note: The checkpoints outside of guideline 6
may be satisfied by assistive technologies as well, but are required by the
current document to be satisfied by a conforming user agent. For example, checkpoint 9.3
involves navigation that must be possible through the user interface, not just
via an API. Note that an assistive technology may be part of the subject of a claim.
To allow user agents with different capabilities to conform, and to
facilitate comparisons of claims about different user agents, this document
defines allows conditional conformance. A user agent conforms conditionally if
it satisfies any set of requirements that results from starting with the default set of requirements and removing or adding
requirements according to these steps:
- Choose a Conformance level; for
conformance levels A or Double-A, remove requirements from the default
- Remove the requirements associated with any unsupported content type labels. In order to conform
conditionally, a user agent must satisfy the requirements of at least one
content type label.
- If the user agent does not satisfy the requirements associated with the Events label, remove those
- If the user agent does not implement a selection mechanism, or if the user agent
does not satisfy the requirements associated with the Selection label, remove those
- Add requirements associated with any supported Input modality label. Note:
In the default set of requirements, the only input device requirements relate
to keyboard input.
- Remove the requirements of any checkpoints or parts of checkpoints that do
Since these steps may produce very different sets of checkpoints for
different user agents, a well-formed conformance
claim must indicate how the set of requirements chosen for the claim
differs from the default set. The checklist
prove useful when documenting the details of a conditional conformance
The following example illustrates how to apply the above steps to determine
which requirements must be satisfied for conformance, and what would be
required as part of a well-formed conformance claim. This informative example does not illustrate a
complete user agent evaluation.
Consider a user agent with these capabilities:
- it supports keyboard and pointing device input;
- it implements:
- one audio format,
- two image formats,
- two other animation formats (besides video, which is considered an
animation format in this document);
- it feeds video to a plug-in for rendering;
- it doesn't support synthesized speech output;
- it implements functionalities to allow keyboard access to event handlers originally designed to
be activated through a pointing device.
- it implements a selection mechanism.
Step 1: Choose a conformance level.
The claimant wishes to conform at level Double-A. This establishes a set of
requirements consisting of all of the requirements of all the priority 1 and 2
Step 2: Identify requirements associated with content type
The claimant wishes to claim conformance for the user agent's support of
images, audio, and video. The claimant does not wish to claim conformance for
other animation formats.
The following content type labels are therefore relevant: Image, Animation,
Video, and Audio. This means that:
- the user agent is not required to satisfy the set of requirements
associated with the Speech content type label. The user agent may still satisfy
some of them.
- the user agent must satisfy the requirements associated with the other
content type labels.
Step 3: Identify requirements related to event handlers.
In this example, the user agent supports functionalities that promote
input-device independent access to event handlers. Therefore, the claimant
may rightly claim conformance for the requirements associated with the Events label.
These requirements are optional for conformance. However, if the claimant
does include the events label in the claim, the associated requirements must be
Step 4: Identify requirements related to the selection.
In this example, since the user agent implements a selection mechanism, it must satisfy the
requirements associated with the
Step 5: Identify requirements associated with any supported
input modality label.
In this example, the claimant does not wish to claim conformance for
complete operation for pointing device or voice input, so no requirements are
added. The user agent may support partial operation through pointing device and
Step 6: Identify requirements of any checkpoints or parts of
checkpoints that do not apply.
Consider checkpoint 4.4, for example, which is associated with both the
Audio and Animation content type labels:
4.4 Slow multimedia.
- Allow the user to slow the presentation rate of rendered
audio and animations (including video
and animated images).
- As part of satisfying provision one, for a visual track, provide at least one
setting between 40% and 60% of the original speed.
- As part of satisfying provision one, for a prerecorded audio track including audio-only
presentations, provide at least one setting between 75% and 80% of the
- When the user agent allows the user to slow the visual track
of a synchronized multimedia presentation to between 100% and 80% of its
original speed, synchronize the visual and audio tracks (per
[#Trespect-sync-cues]). Below 80%, the user agent is not required to render the
- The claimant wishes to claim support for the two image formats, the one
audio format, and the one video format;
- The claimant does not wish to claim support for the other two animation
formats (e.g., because the user agent doesn't satisfy the requirements of checkpoint 4.4
for those animation formats);
- The user agent does not implement any synchronized multimedia formats.
The resulting applicable requirements from this checkpoint would be:
- For the audio format: Allow the user to slow the presentation rate of
audio. For a prerecorded audio track including audio-only presentations,
provide at least one setting between 75% and 80% of the original speed.
- For the video format: Allow the user to slow the presentation rate of
video. For a visual track, provide at least one setting between 40% and 60% of
the original speed.
- For the image formats: None, since the Image content type label does not
- Limitation of scope for any format: The user agent is not required to
satisfy the requirements of this checkpoint for audio and animations whose
recognized role is to create a purely stylistic effect.
The following requirements would not apply:
- When the user agent allows the user to slow the visual track of a
synchronized multimedia presentation to between 100% and 80% of its original
speed, synchronize the visual and audio tracks. Below 80%, the user agent is
not required to render the audio track. Note: The relevant applicability provision is the third one: control of a
content property that the subject cannot recognize. In this case, no format
implemented by the user agent supports synchronized multimedia.
See the section on conformance and implementing
specifications for more information about identifying formats that are used
to satisfy the requirements of this document.
Construct a well-formed conformance claim.
With the information gathered above, it is possible to starting building a
conformance claim. A claim might include the following information:
- Conformance level satisfied: Double-A
- Information about the subject. Both the "main" user agent and the plug-in used to support video must be
identified in the claim (since the plug-in is the component used to satisfy the
requirements for video).
The user agent does not conform
unconditionally, therefore, the claim must also include the following
information (excerpted from a complete claim):
- A general statement about lack of support for the Speech content type
label: "This user agent does not support the requirements of the Speech content
type label. "
- A specific statement about content type support for checkpoint 4.4:
"This user agent satisfies the requirements of the Animation content type label
for the audio format A and the video format V. It does not satisfy the
Animation requirements for animation formats Y and Z."
- A specific statement about support for the Events label: "This user agent satisfies
the requirements related to the Events label."
- A specific statement about support for the Selection label: "This user agent
satisfies the requirements related to the Selection label."
- A specific statement about applicability for checkpoint 4.4:
"The synchronized multimedia requirements of checkpoint checkpoint 4.4
do not apply because the user agent does not implement any formats that support
The following normative subsections provide detail that is relevant to both
unconditional and conditional conformance.
The requirements of certain checkpoints might apply equally well to content
or to user agent user interface features. When it is necessary to remove
ambiguity about the scope of a checkpoint, the checkpoint includes a label to
indicate whether the requirements must be satisfied:
- for content only, i.e., the document object only;
- for user agent features only, i.e., everything that is not content (such as components of the user agent user interface,
user preferences, the user agent documentation, and the user interface focus);
- for both content and user agent features.
Many of the content-only and rendered content-only requirements also make
sense for the user agent user interface (e.g., allow the user to render
blinking text as motionless text). User agent developers are encouraged to
consider the content-only requirements when designing the user agent's user
The user agent may satisfy a content-only or rendered content-only
requirement with a mechanism that also involves user agent features.
For instance, to satisfy checkpoint 4.7, the user agent may provide a single control
for all volume (including content and user interface features). Similarly, to
checkpoint 3.3, the user agent may offer a single configuration that turns
off blinking in both content and the user interface.
In general, a user agent is only required to satisfy the requirements of
this document for a subset of implemented specifications; these
specifications must be named in a well-formed
conformance claim. For example, the user agent may implement ten image
formats, but a developer may only wish to claim "Image" conformance for three of them. In
the well-formed claim, the developer must list the three formats used to
satisfy the Image requirements. The developer is thus "rewarded" for improving
user agent accessibility for three image formats.
There are several checkpoints, however, that must be satisfied for
all applicable implemented specifications,
otherwise the intent of the checkpoint may not be met. For instance, checkpoint
3.3 involves turning off blinking and animated text. Since there is a risk
that these rendering effects may trigger seizures in people with photosensitive
epilepsy, it is important that the user be able to turn them off in all cases
(whether the specification is named in a conformance claim or not).
For a given conformance claim, the user agent must satisfy all checkpoints
in this document for at least those specifications named in the claim (e.g.,
format specifications, style sheet specifications, API specifications,
operating environment conventions, etc.). The user agent is not required to
satisfy all checkpoints for all implemented specifications, except for the
- The user agent must satisfy checkpoint
3.3 for all specifications that cause animated or blinking text effects
(e.g., markup languages or style sheet specifications).
- If the claim includes the Image
content type label, the user agent must satisfy
checkpoint 3.1 and checkpoint 3.6 for all image formats.
- If the claim includes one of the
Animation, Video, Audio content type labels, the user agent
must satisfy checkpoint 3.2 for all animation, video, or audio formats,
- If the claim includes the Audio
content type label, the user agent must satisfy checkpoint
4.7 for all audio formats.
The user agent may satisfy the configuration requirements of this document
through configuration files (e.g., profiles, initialization files, themes,
etc.). For instance, style sheets might be used as a mechanism to satisfy the
highlight and configuration requirements of checkpoint 10.2. Any
functionality that is configurable through a configuration file should also be
configurable through the user agent user
interface. Furthermore, if configuration files may be edited by hand, the
user agent documentation should explain the configuration file format, or refer
to an explanation (a format specification, for example).
For some of the checkpoints in this document (checkpoints 3.3, 5.1, 5.3, and 5.5),
configuration is preferred, but not required to satisfy the checkpoint in some
circumstances. For other checkpoints, the configuration requirement is
considered as important as the functionality being configured.
Since this document allows conformance by multiple software components
(e.g., a browser, a media player, and several plug-ins), there are likely to be
times when, to satisfy the configuration requirements of the document, each
component has to provide for configuration independently. To make configuration
easier for the user, components should share and inherit configurations
(including those of the operating environment).
To satisfy the requirements of this document, developers are encouraged to
environment conventions and features that benefit accessibility. When an
operating environment feature (e.g., the operating system's audio control
feature, including its user interface) is adopted to satisfy the requirements
of this document, it is part of the subject of the
Developers may provide access through the user agent's user interface to
operating environment features adopted to satisfy the requirements of this
document. For example, if the user agent adopts the operating system's audio
control feature to satisfy checkpoint
4.7, the user agent may (but is not required to) include those controls in
its own user interface.
Some of the checkpoints in this document involve operating environment
conventions. When a user agent runs in more than one operating environment
(e.g., a user agent implemented in Java on top of another operating system),
developers may satisfy the requirements of this document by following the
conventions of a single operating environment. Developers should follow the
conventions that benefit accessibility most, while meeting the developers'
design goals. For instance, some developers may prefer cross-platform
consistency over consistency with other user agents running in a given
operating environment, and this might affect which conventions would be
User agents do not conform to this document on a per-resource basis; claims
are not as specific as "the user agent conforms for this particular Web page."
A user agent conforms if it satisfies the requirements of this document for
most general-purpose content, in ordinary operating conditions.
In some cases, the author's content may limit the user agent's functionality
for specific reasons, such as to protect intellectual property rights, or to
provide a read-only view (allowing no user interaction). Content that limits
the functionality of the user agent in some cases does not automatically
invalidate a conformance claim. A valid conformance claim remains valid as long
as the user agent satisfies the requirements of this document for most
Note: The User Agent Accessibility Guidelines Working Group
recognizes that further work is necessary in the area of digital rights
management as it relates to accessibility. Digital rights management refers to
methods of describing and perhaps enforcing intellectual property associated
with Web resources.
Some of the requirements of this document have security implications:
communication through APIs, allowing programmatic read and write access to
content and user interface control, etc. This document assumes that features
required by this document will be built on top of an underlying security
architecture. Consequently, unless permitted explicitly in a checkpoint (as in
6.5), this document grants no conformance exemptions based on security
Consider the example of a form control that allows the user to enter a
password. Graphical user agents commonly display typed characters as asterisks
(or display nothing). The user agent should not communicate asterisks to
assistive technologies, but the real password, properly encrypted.
Appropriate user agent behavior with respect to security (and more generally
as well) also depends on the user's context. For instance, hiding typed
passwords with asterisks is much less important for someone in a room alone
than for someone in a crowded room. Similarly, unencrypted passwords rendered
as synthesized speech should not be broadcast in a crowded room, but may pose
no security risk if the user is wearing an earphone.
For information related to security, refer to "XML-Signature Syntax and
Processing" [XMLDSIG] and "XML Encryption
Syntax and Processing" [XMLENC].
Each conformance level defines a set of requirements, based on priority.
Note: Conformance levels are spelled out in text (e.g.,
"Double-A" rather than "AA") so they may be understood when rendered as
Each content type label defines a set of requirements related to support for
images, animations, video, audio, and synthesized speech.
- This content type label refers to all of the requirements related to images
(excluding animated images) for the following checkpoints: 3.1
and 3.6. To
conform, the user agent must implement at least one image format. The
user agent must satisfy these requirements for all implemented image formats; see the section
on conformance and implementing specifications.
The image requirements apply to
content that is recognized as distinct and
that, according to the encoding format, may be rendered as a coherent
- This content type label refers to all of the requirements related to animations (including video and animated
images) for the following checkpoints: 3.2, 4.4, and 4.5. To
conform, the user agent must implement at least one animation format.
The user agent must satisfy the requirements of checkpoint
3.2 for all implemented animation
formats; see the section on conformance and
implementing specifications. The animation requirements apply to animation
content that is recognized as distinct and
that, according to the encoding format, may be rendered as a coherent
- This content type label refers to all of the requirements related to video
for the following checkpoints: 2.5, 2.6, and 3.2. To
conform, the user agent must implement at least one video format. The
user agent must satisfy the requirements of checkpoint
3.2 for all implemented video formats;
see the section on conformance and implementing
specifications. The video requirements apply to video content that is recognized as distinct and that, according
to the encoding format, may be rendered as a coherent unit.
- This content type label refers to all of the requirements related to audio for the following checkpoints: 2.5, 2.6, 3.2, 4.4, 4.5, 4.7, and
4.8. To conform, the user agent must implement at least one audio format. The
user agent must satisfy the requirements of checkpoints 3.2 and 4.7 for
all implemented audio formats; see the section
on conformance and implementing specifications.
The audio requirements apply to audio content that is recognized as distinct and that, according
to the encoding format, may be rendered as a coherent unit.
- This content type label refers to all of the requirements related to
synthesized speech for the following checkpoints: 4.9, 4.10,
4.12, and 4.13. To conform, the user agent must support synthesized speech.
Note: Some of the labels above require implementation of at
least one format (e.g., for images). This document does not require
implementation of specific formats, (e.g., PNG [PNG]
versus SVG [SVG] for images). However, please see
the requirements of checkpoint 8.2.
The following checkpoints are designed to augment user agent support for
event-driven behavior specified by the author: 1.2,
Satisfying these checkpoints will promote input device independence and thus
enable users with some disabilities to make better use of content designed for
a single input device (generally a pointing device). The
Events label refers to the requirements of these checkpoints.
A conforming user agent is not required to satisfy these requirements.
However, if a user agent does not implement these requirements, then a well-formed claim must say so.
This document does not require the user agent to implement a selection mechanism in order to conform.
However, if the user agent does implement a selection mechanism, in order to
conform it must satisfy the relevant portions of the following checkpoints: 5.4, 6.6, 7.1,
9.4, 10.2, and
The Selection label refers to the selection
requirements of these checkpoints.
If a user agent does not implement a selection mechanism, then a well-formed claim must say so.
Note: This document does require implementation of both content focus and user interface focus; see checkpoint 9.1
Each input modality label defines a set of requirements related to support
for pointing device and voice input. Input device requirements in this document
are either stated generically (e.g., "input configuration" requirements) or as
keyboard-specific requirements (e.g., "keyboard API").
- This input modality label refers to all of the input device requirements of
this document, applied to pointing device input. For keyboard-specific
requirements, substitute "pointing device input" for "keyboard." The set of
pointing device input requirements does not include the requirements of checkpoint 11.4.
- This input modality label refers to all of the input device requirements of
this document, applied to voice input. For keyboard-specific requirements,
substitute "voice input" for "keyboard." The set of voice input requirements
does not include the requirements of checkpoint 11.4.
Note: Developers are encouraged to design user agents that
are at least partially operable through the three input modalities of keyboard,
pointing device, and voice.
A checkpoint (or part of a checkpoint) applies unless any one of the
following conditions is met:
- The checkpoint makes requirements for graphical user interfaces or
graphical viewports and the subject of the claim only has audio or tactile user
interfaces or viewports.
- The checkpoint refers to a role of content (e.g., transcript, captions,
content, synchronization cue, purpose of a table, etc.) that the subject of
the claim cannot recognize because of how the
content has been encoded in a particular format. For instance, HTML user agents
can recognize "
OBJECT content, or
NOFRAMES content as specified mechanisms for conditional content. HTML user
agents are not expected to recognize that a nearby paragraph is a text equivalent for the image (when
not marked up as such).
- The checkpoint requires control of a content property that the subject
cannot recognize because of how the
content has been encoded in a particular format. Some examples of this include:
- captioning information that is "burned" into a video presentation and
cannot be recognized as captions in the presentation format;
- streamed content that cannot be fast forwarded or rewound;
- information encoded in an unrecognized XML namespace;
- information or relationships encoded in
scripts in a manner that cannot be recognized. For instance, the
requirements of checkpoint 3.3 would not apply for animation effects
unrecognized in a script. Some input device behavior may be controlled by
scripts in a manner that the user agent cannot recognize. For example, when the
author uses event bubbling to
dispatch events, the user agent is not likely to recognize the full set of
elements that may receive those events; the user agent is expected to recognize
which element has the explicitly
associated event handler.
A claim is well-formed if meets the following conditions.
Condition 1: The claim must include the following information:
- The date of the claim.
- The guidelines title/version: "User Agent Accessibility Guidelines
- The URI of the guidelines:
- The Conformance level satisfied: "A",
"Double-A", or "Triple-A".
- Information about the subject. The subject of the claim may consist of one
or more software components (e.g., a browser, multimedia player, plug-ins,
documentation, etc.). For each component, the claim must include the following:
- Name and version information for the component. Version information must be
sufficient to identify the user agent (e.g., vendor name, version number, minor
release number, required patches or updates, natural language of the user
interface or documentation). The version information may refer to a range of
user agents (e.g., "this claim refers to all user agents version 6.x").
- Name and version information for the operating environment(s) in
which the component is running.
- Information about which specifications have
been implemented to satisfy the requirements of the document (e.g.,
formats, style sheet languages, APIs, operating environment conventions, etc.)
The information must be sufficient to identify the specification.
Condition 2: The claim must include the following information if the user
agent conforms conditionally:
- Content type labels. Content type labels
are used in assertions that the subject either (1) does not satisfy the
requirements associated with the label (e.g., for a specific checkpoint, for
any checkpoint, etc.), or (2) does satisfy the requirements associated with the
label (e.g., for a particular format when satisfying the requirements of a
checkpoint). In order to conform conditionally, a user agent must satisfy the
requirements of at least one content type label.
- Events label. If the user agent
does not implement these checkpoints related to event handlers, the claim must
- Selection label. If the user
agent does not implement a selection mechanism, or if the user agent
does not satisfy the requirements associated with the Selection label, the
claim must say so.
- Input modality labels. Each input
modality label ("Pointer" or "Voice") is an assertion that the user agent
satisfies the requirements associated with the label.
- A list of requirements (checkpoints or portions of checkpoints) that the
claimant asserts do not apply.
Condition 3: At least one version of the claim must conform to the "Web
Content Accessibility Guidelines 1.0"
[WCAG10], level A. This claim may appear on the Web, on a CD-ROM,
etc. If a conformance icon is part of a claim
on the Web, it must link to the W3C explanation of the icon.
A well-formed claim should also include the following information:
- Rationale for any requirements that do not
This specification imposes no restrictions on the format used to make a well-formed claim. For instance,
the claim may be marked up using HTML (see sample
claim), or expressed in the Resource Description Framework
A conformance claim is valid if the following conditions are met:
- The claim is well-formed.
- It is verified that the user agent satisfies the default set of requirements, in addition to (or
except) those requirements added (or exempted) by the allowable mechanisms: Conformance levels, Content type labels, Input modality labels, and applicability.
It is not currently possible to validate a claim entirely automatically.
- The subject of the claim may consist of more than one software component,
and taken together they must satisfy all requirements that are not excluded
through the claim. These components may run on the user's computer or on a
server. This includes assistive technologies and operating environment features
that are part of a claim. Some components may not have to satisfy some
requirements as long as the subject as a whole satisfies them. For
instance, a particular component of the subject may not have to conform to the
DOM APIs required by guideline 6 as long as the subject of the claim as a whole
makes all content available through those APIs.
- The document has been designed so that non-experts can determine the
validity of a claim. In some cases, a requirement might be clear, but without
documentation or feedback from developers (e.g., about implemented APIs), it may
be difficult to verify that the subject of the
claim has satisfied the requirement. Some checkpoints (e.g., those
requiring developers to follow conventions or implement specifications defined
outside this document) are inherently more open to interpretation than
- Ideally, the default user agent installation procedure should provide and
install all components that are part of a conformance claim. This is because,
the more software components the user must install in order to construct a
conforming user agent, the higher the risk of failure. Failure may be due to
inaccessible mechanisms for downloading and installing
plug-ins, or lack of installation access privileges for a computer in a
public space, etc.
This specification imposes no restrictions about:
- who may make a claim (e.g., vendors about their own user agents, third
parties about those user agents, journalists about user agents, etc.),
- where claims may be published (e.g., on the Web or in paper
Claimants (or relevant assuring parties) are solely responsible for the
validity of their claims, keeping claims up to date, and proper use of the conformance icons. As of the publication of this
document, W3C does not act as an assuring party, but it may do so in the
future, or it may establish recommendations for assuring parties.
Claimants are expected to modify or retract a claim if it may be
demonstrated that the claim is not valid. Claimants are encouraged to claim
conformance to the most recent User Agent Accessibility Guidelines
As part of a conformance claim, people may use a conformance icon (or,
"conformance logo") on a Web site, on user agent packaging, in documentation,
etc. A conformance icon does not represent that a claim is valid, only that a claim has been made. The
appearance of a conformance icon does not imply that W3C has reviewed the
It is inappropriate and meaningless to use a conformance icon on its own,
i.e., to use the icon without an associated
Draft Note: In the event this document becomes a W3C
Recommendation this document will link to the W3C Web site for additional
information about the icons and how to use them.
Authors of technical specifications (such as W3C Recommendations) should
incorporate the requirements of UAAG 1.0 as part of conformance to their
specifications. This may be done by direct inclusion, or by reference using a
conformance profile. Direct inclusion promotes the integration of specialized
accessibility requirements; inclusion by reference is easier and less prone to
- Identify accessibility features of the specification where they are defined
checkpoint 8.1). Optionally, create an appendix of these accessibility
features as well.
- Remember to include user interface requirements as part of conformance to
the specification. Authors of technical specifications tend to focus more on
rendering or other content-related behavior and less on user interface
requirements. UAAG 1.0 makes a number of user interface requirements that
authors will need to consider (such as those in guideline 5
pertaining to viewport behavior).
- Include at least an informative reference to UAAG 1.0 and Techniques for
UAAG 1.0. See the section on how to
refer to UAAG 1.0 for more information.
- When a question arises about how a checkpoint applies for a technology,
whether a term is used differently between UAAG 1.0 and the technical
specification, etc. consult the User Agent Accessibility Guidelines Working
For more information on designing specifications that promote accessibility,
refer to W3C's "XML Accessibility Guidelines"
- Rather than include the generic UAAG 1.0 requirements, tailor them to the
specification. Be specific in the requirements, and include (in context) a
reference to the original UAAG 1.0 checkpoint. The following examples
illustrate what is meant by direct inclusion:
Note how these examples refer to the specific elements, attributes, properties,
etc. of the specifications.
- In an HTML specification, where the
object elements are defined, include a
statement such as "Per checkpoint 3.4 of UAAG 1.0, a conforming user agent must
allow configuration not to execute scripts, applets, or other executable
- In a CSS specification, where the
is defined, include a statement such as "A conforming user agent must either:
(a) allow configuration to override the
'blink' value with the
'none' value, or (b) ignore the
'blink' value. This is required by
3.3 of UAAG 1.0 [UAAG10]."
- It is better to include some UAAG 1.0 requirements in a specification than
no UAAG 1.0 requirements. However, since UAAG 1.0 requirements are designed to
complement one another, arbitrary selection of requirements may result in
accessibility gaps. Authors are encouraged to include requirements according to
the groups defined by the conformance
Section G.5 of the SVG 1.0 Recommendation [SVG]
Additionally, an authoring tool which is a Conforming SVG Generator conforms
to all of the Priority 1 accessibility guidelines from the document "Authoring
Tool Accessibility Guidelines 1.0" that are relevant to generators of SVG
This statement requires conformance to the Authoring Tool Accessibility
Guidelines as part of conformance to SVG 1.0 (for certain classes of tools).
This type of "conformance requirement by reference" is also possible for UAAG
1.0. However, since conditional
conformance to UAAG 1.0 can vary beyond three conformance levels, it is
important for references to state precisely what is required. This is called a
This section explains how to create a valid conformance profile to UAAG 1.0.
UAAG 1.0 does not define any (named) conformance profiles, just the mechanism
for creating them.
A valid conformance profile must include the following information:
- The guidelines title/version: "User Agent Accessibility Guidelines
- The URI of the guidelines:
- The Conformance level to be satisfied:
"A", "Double-A", or "Triple-A".
- Content type labels. The profile must
include at least one content type label. The requirements associated with that
label must be satisfied as part of conforming to the profile.
- Events label. The profile must
indicate whether the requirements associated with this conformance label
(related to event handlers) are part of conformance to the profile.
- Selection label. The profile
must indicate whether the requirements associated with this conformance label
(related to a selection mechanism) are part of conformance to the profile.
A valid conformance profile should include the following information:
- Applicability: Which checkpoints (or portions of
checkpoints) do not apply for this specification. For instance, if a
specification does not define "tables", the conformance profile should indicate
10.1 does not apply. Specification authors should include rationale in
their profiles that explains why a checkpoint does not apply.
A valid conformance profile may include the following information:
- Input modality labels: If conformance
for pointer or voice input is required in addition to keyboard input.
Note: that the following are always required and therefore
need not appear in a conformance profile:
- Keyboard input requirements
- Content focus
requirements (only when the content includes enabled elements; see checkpoint
The following is an (partial) example of a valid conformance profile
(expressed in plain text):
As part of conformance to MyFormat 1.0, a user agent must satisfy the
following conformance profile of the "User Agent Accessibility Guidelines 1.0"
- Conformance level A
- Content type labels: Image, Animation, and Video. This means that a
conforming MyFormat user agent must satisfy the requirements associated with
those labels; refer to UAAG 1.0 section 3.5 for details.
- Selection: A conforming MyFormat user agent must implement a text selection
mechanism, and therefore satisfy the requirements associated with the UAAG 1.0
selection label; refer to UAAG 1.0 section 3.7 for details. A conforming
MyFormat user agent is only required to allow users to select text
- Applicability: The following UAAG 1.0 checkpoints do not apply to MyFormat
and therefore do not need to be satisfied for conformance to this
9.5, 9.6: MyFormat
does not allow inclusion of scripts. Thus, there are no author-supplied event
- 2.4, 2.6: MyFormat
does not involve synchronization.
4.6: MyFormat does not define captions.
MyFormat does not define tables.
- (And so on)
See the section on how to refer to
UAAG 1.0 for what should appear in the references section of the