Accessibility
Journal publishing now entails delivery through a wide range of output devices including
phones, handhelds, eBook readers, and personal computers, as well as the more historically important
print pages and CD-ROMs. Journal articles are provided in a variety of formats including XML,
PDF, HTML, several eBook formats, and DAISY for pronouncing software. At the same time,
governmental regulation, and web best practice as promulgated by the World Wide Web Consortium
(W3C), have led to requirements for better access for the visually and motor impaired. For
papers that fall in the purview of the United States government the relevant accessibility
guidance comes from the Rehabilitation Act of 1973 § 508, as amended by the
Workforce Investment Act of 1998 (P.L. 105 – 220), 29 U.S.C. § 794d
(typically known as Section 508). For the web, the W3C has published the WCAG 2.0: Web
Accessibility Guidelines 2.0 (WCAG 2.0). The two specifications have been declared to
be complimentary, with the techniques of the WCAG 2.0 used to meet the stated Section 508
guidelines. At the level applicable to this Tag Set, both of these accessibility frameworks
concern themselves with how those with impaired sight or motor control operate a website built
for a seeing, fully manipulatory world.
Section 508 deals with such visual and handling aspects as screen flicker, electronic forms,
scripting, and color. The WCAG 2.0 guidelines range from the recommendation that web pages be well
formed, through techniques for pausing and linking, to specifics on web page design. Since the
Journal Article Tag Set does not deal with the look and feel or the behavior of a journal
article, but rather with the intellectual content, many of the Section 508 guidelines and WCAG
2.0 techniques do not apply directly to this Tag Set. But certain elements
and attributes in this Tag Set enable a publisher, archive, author, aggregator, or other
interested party to implement Section 508-compliant or WCAG-accessible display of material based
on XML documents tagged with this Tag Set. The intent is that this Tag SET should not
prevent and should actively enable Section 508 compliance and
WCAG techniques of best accessibility practice.
For example, the Section 508 website (
http://www.section508.gov), under
508 Standards,
Subpart B -- Technical Standards, §
1194.22 Web-based
intranet and internet information and applications (
http://www.section508.gov/index.cfm?fuseAction=stdsdoc#Web), states that
“A text equivalent for every non-text element shall be provided”. This Tag Set
does not require that each graphic, for example, also have a non-text companion, but there are
three enabling elements available within each
<graphic> element to
make that possible. A
<graphic> may contain:
- an <alt-text> element, to hold a brief description of the
graphic for pronouncing software;
- a <long-desc> element, to hold a full description of the
graphic; and or
- an <ext-link> element and/or a <uri> to hold a link to an even more complete description of the
graphic.
This model for a graphic also enables WCAG 2.0: Techniques and Failures for Web
Accessibility Guidelines 2.0 (December 2008) #G73: “Providing a long
description in another location with a link to it that is immediately adjacent to the non-text
content” and #G95 “Providing short text alternatives that provide a brief
description of non-text content.”
Sometimes an abbreviation (
<abbrev>) needs to be
pronounced in a way that is not reflected in its content or its tagging. The
@alt attribute (available on many elements) can be used to record the
pronunciation for screen readers and other accessibility devices. For example, the abbreviation
“WHO” might be better pronounced as “World Health Organization”
(
alt="World Health Organization") or as “W.H.O.” than as the word
“who”. The
@alt attribute can also be used to provide
the textual interpretation of a symbol such as an emoticon (e.g., for “;-)” use an
@alt attribute value such as “
alt="smile-wink"”).
Sometimes a
<label> needs to be pronounced in a
way that is not reflected in its content or its tagging. The
@alt attribute can be used to record the pronunciation for screen readers and
other accessibility devices. For example, the statement label that follows might be pronounced as
“Proof 3”.
<statement>
<label alt="Equation 3">Equation&#x00A0;III.</label>
...</statement>
In the same way, an
<xref> may
need to be pronounced in a way that is not reflected in its content or its
tagging. The
@alt attribute can be used to record the pronunciation
for screen readers and other accessibility devices. For example, the cross-reference to a Statement
label that follows might be pronounced as “Statement 4”.
... See <xref alt="Statement 4">Statement IV.</xref>...
For accessibility purposes, it is useful to provide a very short synopsis abstract
(much like a Table of Contents blurb or a dek in some journals) whose
purpose is to tell a non-sighted reader what the document is about. This
abstract can be given
the
@abstract-type value such
as “
meta-description”, “
description”, or
“
dc:description” to indicate that, when making web
pages from this XML, the abstract can be used to create the XHTML metadata description.
Best practice reserves the
<alt-text> element
for accessibility uses such as pronouncing screen readers. This element should
not be used as a replacement for
<caption>, which is a visual element that is typically displayed alongside a figure,
table, etc. The
<alt-text> is not a visual element,
unless the figure, caption, or other major element that holds the
<alt-text> is not available or cannot be processed by the person
or device-type being addressed. Since it is not visual,
<alt-text> does not allow face markup inside it; a simplified textual alternative for a
graphical object (including face markup) can be created using the
<textual-form> element.
The
<alternatives> element provides a container
for collecting multiple versions of a single graphical or media object. Thus using
<alternatives> can provide a textual alternative to any graphic or
media object or provide an enlarged graphic version for accessibility. By providing this container element for graphical or
media object, this element enables certain W3C Techniques for WCAG 2.0 (December 2008):
- #G58: “Placing a link to the alternative for time-based media immediately next to
the non-text content”
- #G68: “Providing a descriptive label that describes the purpose of live audio-only
and live video-only content”
- #G69: “Providing an alternative for time based media”
- #H86: Providing text alternatives for ASCII art, emoticons, and leetspeak
Here are some additional examples of elements and attributes in this Tag Set that enable
techniques as described in the WCAG 2.0 Techniques and Failures guidelines:
- The @xml:lang attribute was added to the section-level elements and
paragraph-level elements to enable #H58 “Using language attributes to identify changes
in human language”.
- The <ext-link> element, by providing textual
content which can identify the link as well as an explicit URI in an attribute, enables #G53: “Identifying the purpose of
a link using link text combined with the text of
the enclosing sentence” as well as #G91: “Providing link text that describes
the purpose of a link”.
- The long description element (Long Description) was defined as part of elements such as
<fig>, so it can be added not only to all figures
and other graphical objects, but also to many narrative components (for example, to a <boxed-text>) to provide an accessible description of the
object. (The <long-desc> element is available on:
<chem-struct>, <chem-struct-wrap>, <disp-formula>, <disp-formula-group>,
<fig>, <graphic>, <inline-supplementary-material>, <media>, <preformat>, <supplementary-material>, and <table-wrap>.)