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Version 1.2
February 14, 2002
Preface
In an effort to address the needs of all users, the Illinois Technology Office
has established the Illinois Web Accessibility Standards (IWAS). On February
14, 2002, the Governor signed an Administrative
Order directing Illinois agencies to "utilize the Illinois Web Accessibility
Standards for the development of web sites, intranets, and web-based applications."
These standards are based on Federal "Section
508" and World Wide Web Consortium
accessibility guidelines, which were reviewed extensively by a panel of experts
during the preparation of IWAS. You may wonder why the Illinois Technology Office
has created an additional set of standards when the Section 508 and W3C standards
already exist. The answer is quite simple: The federal Section 508 guidelines
deal with a very basic level of accessibility needs while leaving out many issues
facing users. The W3C guidelines, on the other hand, offer three tiers of priorities
that go into greater depth than many government entities are able to address
at this time. IWAS incorporate a combination of the two creating a standard
well suited to serve the users of Illinois web sites.
Contents:
Introduction
Purpose
The Illinois Web Accessibility Standards are designed to provide practical
and specific guidence for the development of web sites, intranets, and web-based
applications that are accessible to Illinoisans with disabilities.
Audience
These standards are intended for use by all web authors, developers, and content
contributors creating or maintaining web pages for the State. The basic concepts
should be understandable by anyone with a general familiarity with web technologies.
Knowledge of Hypertext Markup Language (HTML) and related web languages will
help in fully understanding the Implementation Guidelines.
Scope
These standards include:
- Performance Criteria - a concise list of functional goals that must be achieved
for a web site to be considered accessible.
- Implementation Guidelines - the detailed techniques for addressing accessibility
using current web technologies.
Both Performance Criteria and Implementation Guidelines are necessarily technology-dependent
and will be updated as technologies evolve and change. The web technologies
considered the current standards as of this version include:
- Hypertext Markup Language (HTML) 4.01
- Extensible Hypertext Markup Language (XHTML) 1.0
- Cascading Style Sheet (CSS) Level 1 & 2
- Document Object Model (DOM) Level 1
- Synchronized Multimedia Integration Language (SMIL) 1.0
- JavaScript & Dynamic HTML (DHTML)
Note: The use of other technologies (e.g., Java, Flash) and other document
formats (e.g., Adobe Acrobat PDF, Microsoft Word, WordPerfect) is permissible
if used in accordance with the standards outlined in this document. See the
sections on Applets and Plug-ins and Downloadable Documents for more information.
Relation
to Existing Accessibility Standards
The Illinois Web Accessibility Standards build on two sets of existing standards:
The Illinois Web Accessibility Standards are designed to meet or exceed all
Federal Section 508 requirements and all WCAG "Priority 1" Checkpoints.
The Illinois Standards exceed the minimum requirements in many areas, incorporating
a number of WCAG "Priority 2" and "Priority 3" Checkpoints
as well as additional requirements identified through practical experience working
with Illinoisans with disabilities. Each Guideline in the Illinois Standards
includes a reference to the corresponding Section 508 requirements and WCAG
Checkpoints.
Individuals with disabilities use a variety of accessibility techniques and
assistive technologies to access web-based information. From a practical standpoint,
web sites must therefore be compliant and compatible with these accessibility
tools in order to be accessible to people with disabilities. From this perspective,
the following functional performance criteria can be used to judge whether accessibility
is effectively achieved:
Implementation
Guidelines:
1. Coding
1.1 - Use valid, standard web programming code.
- What:
- The World Wide Web Consortium (W3C) sets and publishes standards for most
web programming languages, including HTML 4.01, XHTML 1.0, CSS Level 1 &
2, DOM, and SMIL. Programming code is considered "valid" when it
follows the all the rules and conventions specified in the published standards.
- Why:
- Screen readers and other assistive technologies can more accurately interpret
and interact with web pages that are built using valid, standard code. W3C
languages are designed with accessibility in mind.
- How:
- Indicate the programming language you are using by starting your code with
a document type declaration such as:
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
Use the W3C HTML Validation Service
(http://validator.w3.org) and W3C
CSS Validation Service (http://jigsaw.w3.org/css-validator) to check your
code. Refer to the World Wide Web Consortium
site (http://www.w3.org) for full specifications and documentation.
- Ref:
- WCAG 3.2, 11.1
1.2 - Use appropriate markup to convey document structure.
- What:
- HTML includes markup (programming code) to identify the structural elements
of a document. For example, the
<p> element identifies
a paragraph and <h1> identifies a first-level heading.
- Why:
- Screen readers use structural elements to help make reading more efficient.
For example, some screen readers can skip from heading to heading to allow
the user to "skim" the document.
- How:
- Identify section heading, paragraphs, lists, quotes, etc using the appropriate
tags instead of relying on formatting commands to distinguish these elements.
For example, use
<h1> tags to identify top-level headings
rather than simply applying font-size or bold formatting commands. Do not
misuse structural elements for formatting effects, such as using <h1>
to make text bold or <blockquote> to indent a paragraph
that is not actually a quotation.
- Ref:
- WCAG 3.5, 3.6, 3.7, 5.4
1.3 - Use style sheets for formatting whenever possible.
- What:
- Cascading Style Sheets (CSS) is a formatting language designed to compliment
HTML. While HTML is designed to identify a document's structure, CSS is intended
for formatting and presentation.
- Why:
- In general, users can most easily override formatting settings made using
CSS. The use of CSS for formatting also tends to facilitate the proper use
of HTML to identify document structure.
- How:
- See the W3C's Cascading Style Sheets
site (http://www.w3.org/Style/CSS/) for specifications, tutorials, and
resources.
Note: Some older web browsers, notably Internet Explorer 3 and Netscape 4,
have problematic support for CSS. Be sure to test pages using CSS in multiple
browsers.
- Ref:
- WCAG 3.3
2. Text
2.1 - Avoid using images to display text.
- What:
- Web developers often use images of text to achieve a specific style, size,
or special effect.
- Why:
- Users with limited vision rely on the ability to enlarge text or choose
enhanced color combinations. However, most web browsers cannot change the
size and color of images.
- How:
- Whenever possible, use actual text instead of images of text. Style sheets
can be used to achieve specific sizes, colors, or effects. Text that requires
exact formatting, such as logos, are appropriate exceptions.
- Ref:
- WCAG 3.1
2.2 - Avoid using absolute sizes for fonts.
- What:
- Font sizes can be set using "absolute" or "relative"
units of measurement. Absolute units, notably pixels, points, and inches,
are based on fixed physical measurements; "relative" units, such
as percentages or "
small," "medium,"
or "large," are based on the user's default font size.
- Why:
- Users with limited vision often rely on the ability to enlarge text. Most
web browsers allow users to easily change the size of text that has been set
with relative units (or not set at all). Using absolute font sizes generally
makes it much more difficult for users to change text size to meet their needs.
- How:
- Set font sizes using relative measurements or avoid setting font sizes altogether.
Note: The "em" unit is another useful relative measurement; however,
Internet Explorer 3 incorrectly interprets em's as pixels.
- Ref:
- WCAG 3.4
2.3 - Specify the language of text.
- What:
- HTML uses the
lang attribute to specify language in a web page.
It can be set for any HTML element.
- Why:
- Words written in foreign languages can be unintelligible when spoken by
a screen reader. Some screen readers are able to pronounce words in their
appropriate language if it is specified.
- How:
- Use the
lang attribute on the <html> element
to identify the primary language of each document, for example, <html
lang="en">, for English.
Use the lang attribute on <span> or other
elements to identify words or phrases in other languages. For example, a Spanish
phrase within an English document could be coded as <span lang="sp">se
habla español</span>.
Note: Not all screen readers support automatic language changes, but setting
the lang attribute will not negatively affect those that do not.
- Ref:
- WCAG 4.1, 4.3
2.4 - Avoid using "ASCII art."
- What:
- "ASCII art" (and "emoticons") are images created using
special arrangements of text characters and symbols. For example, ":-)"
is often used to create a smiley face, and "->" is often used
as an arrow.
- Why:
- Screen readers read most ASCII art literally, which can be extremely confusing.
For example, ":-)" reads as "colon dash right parenthesis,"
and "->" as "dash greater than."
- How:
- Use images with appropriate alternate text instead of ASCII art.
- Ref:
- n/a
3. Colors
3.1 - Do not convey information with color alone.
- What:
- Color is often used to indicate special functions or status. For example,
required form fields are frequently indicated with red labels.
- Why:
- Users with blindness, limited vision, or color-blindness may miss information
presented with color.
- How:
- Whenever color is used as an indicator, use a non-color-based indicator
as well. For example, required form fields could be identified with asterisks
as well as color.
- Ref:
- WCAG 2.1; 508 c
3.2 - Use contrasting foreground and background colors.
- What:
- Web authors can set specific colors to be used for foregrounds (text) and
backgrounds. Sometimes images are used as backgrounds.
- Why:
- Users with limited vision or color-blindness may have difficulty reading
text that is similar in color to its background.
- How:
- For text, use dark colors on light backgrounds, or vice versa. Avoid combinations
of red and green as well as busy background images.
- Ref:
- WCAG 2.2
4. Images
4.1 - Provide "alternate text" for all images.
- What:
- The HTML image element (
<img>) includes an "alternate
text" attribute (alt) that is used to provide text that
can be substituted when the image itself cannot be displayed. Alternate text
is meant to be a concise replacement for an image and should serve the same
purpose and convey the same meaning.
- Why:
- Individuals who are blind cannot perceive information presented in images;
screen reading software reads alternate text instead.
- How:
- ALL images must have appropriate alternate text. As a rule of thumb, consider
what you might say if you were reading the web page to someone over the telephone.
You do not need to include the words "image of" or "graphic
of."
Specifically:
- For images that contain words or letters - use alternate text that includes
the same words or letters.
- For images links - use alternate text that identifies the link's destination
or function. You do not need to include the words "link to."
- For images that are invisible, purely decorative, or otherwise do not
convey meaning - use
alt="" (null) to indicate
that the image can be safely ignored by a screen reader.
- Ref:
- WCAG 1.1; 508 a
4.2 - Provide full descriptions for graphs, diagrams, and
other meaningful images.
- What:
- "Meaningful" images are images that convey more information than
can appropriately be expressed as alternate text.
- Why:
- A full description allows a user who cannot see or understand a meaningful
image to receive the same information as a sighted individual.
- How:
- Present a full description of a meaningful image either on the page on which
the image appears or through a link immediately preceding or following the
image. Use alternate text to provide a concise name for the image. For example,
the alternate text of a graph should state its title and the long description
should summarize its trends and/or present a table of its data.
Note: The longdesc attribute of the <img>
element can also be used to provide a link to a full description. Because
longdesc it is not yet supported by most web browsers, it should not be used
as the only method of providing a full description.
- Ref:
- WCAG 1.1; 508 a
5. Image Maps
5.1 - Provide alternate text for each area in client-side
image maps.
- What:
- Image maps are images divided into multiple "areas," with each
area having its own hypertext link.
- Why:
- Just as images must have alternate text, each area of an image map must
also have appropriate alternate text for use when the image is not displayed.
- How:
- Use alternate text that indicates the function or destination of the link
for each area of a client-side image map. The image itself should have alternate
text that indicates the overall function of the image map.
- Ref:
- WCAG 1.1; 508 a
5.2 - Avoid using server-side image maps.
- What:
- While client-side image maps and server-side image maps look and operate
similarly, they are technically very different. Because of the way server-side
image maps work, all information about the image and links is stored at the
web server and is not available to the user's web browser or assistive technology.
- Why:
- Screen readers cannot identify or read the separate areas or links within
server-side image maps.
- How:
- Whenever possible, use client-side image maps instead of server-side image
maps. If server-side image maps must be used, provide a set of text links
that duplicate all the functions/destinations included in the image map.
- Ref:
- WCAG 1.2, 9.1; 508 e, f
6. Audio
6.1 - Do not convey information with sound alone.
- What:
- It is possible to use sound for a variety of purposes, including presenting
warning signals, cues, or verbal instructions.
- Why:
- Users who are deaf or hard of hearing may miss information provided only
through sound.
- How:
- Whenever significant information is provided by sound, include a visual
indicator that provides the same information as well.
- Ref:
- WCAG 1.1; 508 a
6.2 - Provide text transcripts for audio containing speech.
- What:
- "Audio containing speech" includes audio recordings or live broadcasts
of speeches, seminars, conferences, etc. A text transcript is a word-for-word
written record of the spoken content of such an event.
- Why:
- Individuals who are deaf or hard of hearing may require text transcripts
to access audio information.
- How:
- Provide a link to a text (or HTML) transcript of any audio presented on
a web site. Transcripts should be posted at the same time the audio is made
available. Computer-Aided Real Time (CART) captioners can transcribe live
events.
- Ref:
- WCAG 1.1; 508 a
7.1 - Provide synchronized captions for multimedia containing
speech.
- What:
- Multimedia generally refers to recorded or live media containing both video
and audio tracks. Captioning (as in "closed captioned") is essentially
a text transcript of the audio synchronized with the audio/video tracks of
the presentation.
- Why:
- Individuals who are deaf or hard of hearing may require captions to access
the audio information in multimedia.
- How:
- Whenever possible, captions should be implemented using Synchronized Multimedia
Integration Language (SMIL) to synchronize the display of text from a transcript
with the video. As a less desirable alternative, captions can be added to
a standard video recording and then converted to a web format.
- Ref:
- WCAG 1.4, 508 b
7.2 - Provide audio descriptions for multimedia with significant
video.
- What:
- Audio descriptions are verbal descriptions of the actions and images displayed
in a video that are inserted during pauses in the regular dialog or audio
track. Audio descriptions are only necessary if significant information that
is presented visually is not discernable from the dialog or audio track.
- Why:
- Individuals who are blind or low-vision may require audio descriptions to
access the visual information in multimedia.
- How:
- Carefully consider whether audio descriptions are necessary to present the
significant information of a multimedia recording. Many speech-intensive events,
such as speeches, lectures, or conferences, may not need audio description.
- Ref:
- WCAG 1.3
8. Animation
8.1 - Avoid flickering, blinking, and unnecessary animation.
- What:
- Animated graphics, Flash, Java,
<blink> tags, <marquee>
tags, and other techniques are often used to create a variety of animated
effects.
- Why:
- Flickering or blinking between 2 and 55 Hz (flashes per second) can trigger
epileptic seizures. Animation can be distracting to users with certain visual
or cognitive disabilities.
- How:
- Do not cause elements to blink regularly between 2 and 55 Hz. Avoid animation
and movement unless it provides significant additional information.
- Ref:
- WCAG 7.1, 7.2, 7.3; 508 j
9. Links
9.1 - Make sure that links are understandable out of context.
- What:
- A link is understandable out of context when it clearly indicates its destination
or function without requiring additional information.
- Why:
- Screen reader users often tab through links (skip from link to link by pressing
the Tab key) in order to "scan" a page. Most screen readers also
offer a "links list" feature to help speed the process of navigating
to specific links. Links that are not understandable out of context, such
as "click here" or "more," make these techniques much
less efficient.
- How:
- Use link text that is clear and unambiguous. Avoid using "click here."
- Ref:
- WCAG 13.1
9.2 - Provide a means of skipping past repetitive navigation
links.
- What:
- Navigation links are the lists or "menus" of links to all the
sections of a site that are often repeated on every page.
- Why:
- Because navigation links are typically placed at the beginning (top left)
of pages, screen reader users must read through all the navigation links before
reaching the main area of the page. Individuals who use a keyboard instead
of a mouse similarly must tab through all the navigation links before reaching
the main area of the page. Providing a means of skipping these links can significantly
improve efficiency and usability for screen reader and keyboard users.
- How:
- Provide a link at the beginning of navigation lists that points to a target
at the beginning of the main content area of the page. This link must be visible
to screen reader and keyboard users, but can be hidden from other users. It
is also acceptable to design a page so that navigation links come at the end
of the document.
- Ref:
- 508 o
9.3 - Avoid using small images or text as links.
- What:
- The size of the "clickable" area of a link is limited to the size
of the image or text that makes up the link.
- Why:
- Mouse-users with limited fine motor control may have difficulty pointing
to and clicking on links that are small, especially if the links are close
together.
- How:
- Make sure that images used for links are reasonably large, preferably 32
pixels by 16 pixels or larger. Use standard or enlarged font sizes for text
links, and avoid using text links that are shorter than four characters in
length. Additionally, avoid placing small links close together.
- Ref:
- n/a
10.1 - Associate labels with all form fields.
- What:
- HTML forms include "fields" such as buttons (
<input type="button">),
text boxes (<input type="text">), list boxes
(<select>), and more. Each field is typically identified
by a text label.
- Why:
- Screen readers cannot always determine which label belongs to which field
based on positioning alone. The
<label> element makes this
association clear.
- How:
- Use the
<label for=""> tag to label every form
field.
Note: The value of a label's for attribute is the corresponding
field's id, not its name.
- Ref:
- WCAG 12.4; 508 n
10.2 - Position labels as close as possible to form fields.
- What:
- Using certain layout techniques, form labels are not always positioned immediately
next to their fields.
- Why:
- When screen magnification software enlarges a web page it also reduces the
field of view. If form field label is positioned far away from its field,
it may be impossible for a screen magnifier-user to view both the field and
the label at the same time.
- How:
- Position labels immediately adjacent to fields, preferably in standard locations,
such as on the left or above text boxes and list boxes and on the right of
checkboxes and radio buttons.
- Ref:
- WCAG 10.2; 508 n
10.3 - Include any special instructions within field labels.
- What:
- Frequently, special instructions are listed after the field to which they
apply. In some cases, instructions are even presented in "pop up"
text or in the browser's status bar.
- Why:
- When filling out a form, screen readers typically read only the field's
label. Screen magnifiers will focus on the field and its label, and instructions
may be out of the field of view.
- How:
- Special instructions should be given before the form field and within the
field label if possible. If instructions are too long to appropriately fit
within the label, they should be given in an instructions section in advance
of the form.
- Ref:
- 508 n
10.4 - Make sure that form fields are in a logical tab order.
- What:
- Screen reader and keyboard users move between form fields (and links) using
the Tab key. The order in which form fields receive focus is called the tab
order. By default, the tab order follows the order in which elements appear
in a page's HTML code.
- Why:
- Depending on the design and layout of a page, the tab order may not match
the visual (or logical) order of fields on a form. Reading fields out of their
intended order can be disorienting for a screen reader or keyboard user.
- How:
- Make sure that fields appear in the HTML code in the logical order and/or
use tabindex to set the appropriate order.
Note: Tabindex only is supported by Internet Explorer 4 and up.
- Ref:
- WCAG 9.4; 508 n
11. Data Tables
11.1 - For simple data tables, explicitly identify headings
for all columns and rows.
- What:
- "Data tables" are simply HTML tables used to display data. (On
the other hand, "layout tables" are used to lay out columns and
sections on a web page. Both data and layout tables use the
<table>
element, but their functions, and accessibility issues, are very different.)
"Headers" identify the content of each row and/or column.
- Why:
- A screen reader can use table headers to provide row and column information
while a user explores the data cells within a table.
- How:
- Use
<th> (table header) or <td> (table
data) elements with scope="col" (for column headers)
or scope="row" (for row headers) to identify cells
that contain row and/or column headings.
- Ref:
- WCAG 5.1; 508 g
11.2 - Avoid using complex data tables.
- What:
- Table with multiple layers of headers and "spanned" columns or
rows can become very complex.
- Why:
- Complex data tables can be difficult to navigate and understand using a
screen reader. Only the most advanced screen readers can use advanced table
markup to provide orientation information.
- How:
- Whenever possible, simplify complex tables by re-arranging or dividing them
into separate tables. When a complex table cannot be simplified, use advanced
table markup, such as headers, axis, scope,
<col>, and
<colgroup>, to fully indicate the relationships between
data cells and headers.
Note: See W3C's
"Tables in HTML Documents" (http://www.w3.org/TR/html401/struct/tables.html)
for complete details on how to markup complex tables.
- Ref:
- WCAG 5.2; 508 h
12. Frames
12.1 - Provide meaningful names and page titles for all
frames.
- What:
- HTML frames are used to divide web pages into separate areas, each displaying
a separate web page. Each frame is identified by a
name attribute
and each page contained within a frame is identified by its <title>
element.
- Why:
- To navigate pages with frames, users who are blind must be able to identify
the different frames and understand the purpose of each frame. Most screen
readers identify frames by speaking the name and/or page title of each frame.
- How:
- Give each frame an understandable name that indicates the frame's function.
For example, use
name="Navigation" and name="Content"
rather than name="nav" and name="right".
Set the <title> element of each page contained within a
frame to match the name attributes or to identify the current
content of that frame.
Note: Traditionally, the "name" attribute is used for
programming and should not contain spaces; the title attribute,
which can contain spaces, can also be used to set a more descriptive name
for each frame; however, this technique is not yet supported by all screen
readers.
- Ref:
- WCAG 12.1; 508 i
12.2 - Avoid using empty or non-essential frames.
- What:
- Frames are sometimes used inappropriately for formatting and layout. For
example, empty frames can be used to create margins around or within a page.
- Why:
- Screen readers cannot judge whether the content of a frame is significant
and must identify every frame for the user. Having to read this extraneous
information for non-essential frames can be time consuming and confusing.
- How:
- Use frames sparingly. If a frame is not necessary for page content, eliminate
it.
- Ref:
- n/a
13. Scripts
13.1 - Make sure that significant interactions can be performed
with both keyboard and mouse.
- What:
- Scripting languages, such as JavaScript, are simple programming languages
that can be used within a web browser to automate certain tasks and enable
pages to change and respond to user input. Scripts can trigger changes when
the user performs specific actions ("events"). Some events are triggered
by either mouse or keyboard actions. For example, an image can change color
when the mouse pointer hovers over it (the onmouseover event).
- Why:
- Users with physical impairments may be able to use the keyboard but not
the mouse. Individuals who cannot see the mouse pointer on the screen also
use the keyboard for all interactions. Scripts that can only be triggered
by the mouse are not usable by these individuals.
- How:
- Whenever using a mouse-only event (e.g., onmouseover, onmouseout) to trigger
a significant script action, also use the corresponding keyboard event (e.g.,
onfocus, onblur). Also make sure that keyboard events do not unintentionally
trigger script actions. For example, keyboard users should be able to arrow
through the choices in a
<select> list without triggering
each choice (e.g., onchange).
- Ref:
- WCAG 6.4, 9.2, 9.3
13.2 - Make sure that essential content and functionality
are available when client-side scripts are not fully supported.
- What:
- Scripts are often used to dynamically show or hide the content that appears
on a web page or to perform important functions, such as checking that entries
in form fields are appropriate. "Client-side" scripts, such as JavaScript,
are scripts that are run by the user's web browser. Client-side scripts must
be supported by and compatible with the user's browser in order to work. ("Server-side"
scripts, such as CGI, ASP, JSP, or PHP, run on the web server before the web
page ever reaches the user's browser. Server-side scripts do not generally
pose additional accessibility problems.)
- Why:
- Older assistive technologies and web browsers may not support client-side
scripting at all. Even current assistive technologies may interact in unexpected
ways with content that is displayed using scripts, such as by skipping text
that is dynamically displayed or reading text that is dynamically hidden.
Users need to be able to access the same essential content and functionality
whether scripts are fully, partially, or not supported. It is not safe to
assume that users with disabilities will have scripting support turned off.
- How:
- Whenever scripts are used, it is the responsibility of the page developer
to thoroughly test using assistive technologies to ensure that all information
and functionality is accessible. If there is any doubt, err on the safe side
by ensuring that the essential elements of the page do not rely on scripts.
Note: One approach to ensuring accessibility with scripts is to include a
back-up method of providing the same information and functionality that does
not require scripts. For example, if a client-side script is used to check
an entry in a form field, a server-side script could make the same check.
Similarly, if scripts are used for "drop-down" menus, the same menu
choices could be provided in an appropriate location elsewhere on the current
or subsequent page. Additionally, scripting features that are purely decorative
and do not present any significant information or functionality do not need
to be made accessible. (However, remember Guideline 8.1 - Avoid flickering,
blinking, and unnecessary animation.)
- Ref:
- WCAG 6.3; 508 l
14.
Applets and Plug-Ins
14.1 - Use accessible applets or plug-ins whenever possible.
- What:
- "Applets" and "plug-ins" refer to a variety of newer
web technologies, such as Java and Flash, that can be used to create advanced,
interactive content on web pages. Both require additional software to be downloaded,
installed, and run before the content can be viewed or used. Applets and plug-ins
also operate with their own user interfaces, which are separate and different
from that of standard web pages.
- Why:
- Because applets and plug-ins have their own interfaces, they must be accessible
in and of themselves. If essential content or functionality is presented using
an applet or plug-in that is not accessible, it will not be usable by individuals
with disabilities.
- How:
- Check with the manufacturer and/or developer of each applet or plug-in to
determine if and how the technology is accessible. When an accessible applet
or plug-in is available, provide users with a link to any special instructions
or software that is necessary.
- Ref:
- WCAG 8.1; 508 m
14.2 - If an inaccessible applet or plug-in must be used,
provide an accessible alternative that includes the same content and functionality.
- What:
- If an applet or plug-in is inaccessible, it may be possible to provide both
the original applet or object and an equivalent accessible alternative.
- Why:
- The same features that make an applet or plug-in inaccessible to some users
may actually improve accessibility or usability for users without, or with
different, disabilities. By providing both the original and accessible versions,
the same content and functionality can be available to all users.
- How:
- Wherever a link is provided to an inaccessible applet or object, also provide
a link to an equivalent accessible version. Make sure that the information
and functionality is completely equivalent and up-to-date. Be sure to consider
whether the inaccessible version is actually necessary.
In cases where it is impossible to create an equivalent accessible version,
such as with some geographical imaging and mapping systems, exceptions may
be necessary.
- Ref:
- WCAG 6.2, 11.4; 508 k
15.
Downloadable Documents
15.1 - Provide accessible HTML or text versions of downloadable
documents whenever possible.
- What:
- Downloadable documents are often provided in formats such as Adobe Acrobat
PDF, Microsoft Word, or WordPerfect. Such documents must be viewed in their
own applications or using a web browser plug-in.
- Why:
- The applications required to open downloadable documents may not be available
or accessible to users with disabilities.
- How:
- Wherever a link is provided to a document that is not HTML or text, also
provide a link to an accessible HTML or text version of the same document.
HTML versions should follow these guidelines; text versions may require reformatting
to ensure proper reading order, and additional text descriptions may need
to be added for charts, graphs, or other non-text content.
Note: Adobe is actively improving the accessibility of PDF documents, however,
the process for making existing PDF documents accessible is complex, and the
accessibility features are not yet completely supported. (See access.adobe.com
for more information as well as Adobe's online PDF to HTML conversion tools.)
- Ref:
- n/a
15.2 - If a downloadable document cannot be provided in
an accessible electronic format, provide information on how to request an alternate
format.
- What:
- In some cases, documents cannot be provided in electronic format.
- Why:
- Users with disabilities must still have equivalent access to public documents.
- How:
- Provide information regarding whom to contact to obtain the document in
alternate formats (e.g., braille, large-print, or audio-cassette). Alternate
formats must be available in a timely manner.
- Ref:
- n/a
16. Window
Control
16.1 - Notify users of actions that will open a new window.
- What:
- It is possible to cause hypertext links to open pages in a new browser window,
or to automatically open additional windows when a page loads or unloads.
- Why:
- It may not always be obvious to users, especially those with limited vision,
blindness, or cognitive disabilities, when a new window has opened. It can
be confusing when features such as the browser's "back" button no
longer work as expected.
- How:
- Avoid automatically opening new windows. Clearly identify any links that
will open new windows by providing an indication in the link text or
title
attributes.
- Ref:
- WCAG 10.1
16.2 - Do not automatically refresh the current page.
- What:
- It is possible to cause web pages to automatically re-load their content
on a certain interval. For example, a page containing news headlines might
refresh every few minutes to present the most current items.
- Why:
- When a page automatically refreshes, it can cause a screen reader to re-start
reading from the beginning of the page.
- How:
- Do not use
HTTP-EQUIV="refresh". If necessary, provide
a link or control to allow the user to refresh a page at his or her discretion.
- Ref:
- WCAG 7.4
16.3 - Notify users of time limits and provide a means to
extend time if needed.
- What:
- Some web pages, frequently those that require a user to log in with an ID
and password, "reset" themselves after a certain period of inactivity.
Typically, any form entries that have been partially completed are erased
and the user must start over.
- Why:
- Users with visual, physical, or cognitive disabilities may require more
time than average to read and interact with a web page.
- How:
- Provide a clear explanation of any time limits and offer the user a way
to extend or remove the limits if necessary. Avoid using time limits unnecessarily.
- Ref:
- WCAG 7.5; 508 p
17. Page Layout
17.1 - When using tables for layout, make sure that reading
order is logical.
- What:
- Layout tables are HTML tables used to lay out a web page in multiple columns
and sections (as opposed to tables that actually present data.) "Reading
order" refers to the order in which a screen reader would read through
the table. For example, the reading order for a simple table might be (1)
row 1, cell 1, (2) row 1, cell 2, (3) row 2, cell 1, and (4) row 2, cell 2.
- Why:
- Screen readers read through tables in the order in which cells are defined
in the table code, which can be very different from the order that someone
reading visually would follow. It is essential that the reading order match
the logical flow of the document so that a screen reader user would hear the
document in the same order that a visual reader would read it.
- How:
- Check the reading order by following the order in which the table cells
appear in the code. It may be possible to combine cells and/or nest tables
to achieve an appropriate reading order.
- Ref:
- WCAG 5.3
17.2 - When using style sheets for layout, make sure that
reading order is logical when style sheets are not supported.
- What:
- The positioning features of Cascading Style Sheets can be used to position
elements visually almost anywhere on a web page.
- Why:
- As with layout tables, screen readers read through the elements on a web
page in the order in which they appear in the page code, regardless of how
they are positioned using style sheets. It is essential that the reading order
match the logical flow of the document so that a screen reader user would
hear the document in the same order that a visual reader would read it.
- How:
- Check the reading order by following the order in which elements appear
in the page code. Reading order can usually be adjusted by rearranging the
order in which elements are defined in the code.
- Ref:
- WCAG 6.1; 508 d
17.3 - Minimize the need for horizontal scrolling.
- What:
- If a web page is wider than the window or screen in which it is viewed,
most browsers will display a horizontal scroll bar and require the user to
manually scroll to see the entire page.
- Why:
- When a screen magnifier enlarges a web page, it also reduces the field of
view so that the user must pan (scroll) to see the entire page. When the web
page being viewed also requires horizontal scrolling, the combination can
be awkward or unusable. Keyboard users may also find repetitive scrolling
fatiguing and inefficient.
- How:
- Design pages so that they can resize to fit the width of the user's browser.
Use relative widths on tables and frames used for layout and make sure that
horizontally adjacent images are less than a total of 600 pixels wide. If
scrolling cannot be avoided, place the least important content in the rightmost
part of the page.
- Ref:
- WCAG 3.4
18. Page Content
18.1 - Use the clearest, simplest, and most concise language
appropriate for a page's subject matter.
- What:
- "Clearest, simplest, and most concise language" refers to the
words and grammar used in the content of a web page. It is a subjective goal
that depends on the subject matter and intended audience of each web page.
- Why:
- Clear and simple language is easier for all readers, and especially those
with cognitive or learning disabilities. Simple language also helps individuals
whose primary language is American Sign Language, which differs significantly
from written English.
- How:
- Be concise and avoid jargon. Have someone else proofread your text. Do user
testing with people from your intended audience if possible.
- Ref:
- WCAG 14.1
19.
Alternate Accessible Versions
19.1 - Use separate accessible versions only as a last resort.
- What:
- Separate accessible or "text-only" versions are often offered
instead of providing a single accessible site.
- Why:
- Manually developing and maintaining a separate "text-only" version
of an entire site is tremendously demanding of time and resources. In practice,
"text-only" versions are rarely kept complete or up-to-date. Given
advances in accessibility techniques and assistive technologies, "text-only"
sites are simply not necessary in most cases.
- How:
- Follow these standards to develop a single site that is universally accessible
and efficient to maintain.
- Ref:
- WCAG 11.4; 508 k
20.1 - Provide contact information.
- What:
- A contact person for accessibility issues should be identified. Contact
information should include email, telephone, TTY, and mailing address.
- Why:
- Individuals with disabilities may need to report accessibility problems
or request information in an alternate accessible format.
- How:
- List accessibility contact information on the home page or contact page.
Inquiries about accessibility, especially requests for materials in alternate
format, need to be handled in a timely manner. This contact information should
also be provided to the Illinois Technology Office (see Credits
& Contacts below).
- Ref:
- n/a
21. Testing
21.1 - Test for accessibility.
- What:
- Testing includes functional tests with assistive technology, browser and
operating system functionality as well as automated testing software.
- Why:
- Testing will determine whether accessibility has actually been accomplished.
- How:
- Use browser and operating system accessibility features and leading assistive
technology software such as screen readers and magnifiers to test for functional
accessibility. Use an automated testing tool like Bobby
(http://www.cast.org/bobby) to identify common accessibility problems. If
possible, do user testing with people with disabilities.
- Ref:
- n/a
- Author:
- Mike Scott, MSF&W Information Technology Solutions
- Contributors:
- Patrick Beaird, Illinois
Technology Office
Jon Gunderson, University of Illinois
at Urbana-Champaign, Center for Instructional Technology Accessibility
Wilhelmina Gunther, Illinois Assistive Technology
Project
For questions, comments, or suggestions regarding the Illinois Web Accessibility
Standards, contact the Illinois Technology Office:
Illinois Technology Office
2½ State House
Springfield, Illinois 62706
Telephone: (217) 524-5113
TDD: (217) 782-2239
Email: webmaster@state.il.us
Web: http://www.illinois.gov/ITO/
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