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What is math accessibility?

Learning Points:

Defining accessibility

We often use the terms "access" and "accessible" in various ways, depending upon the context of our discussion. It is not uncommon to hear someone talk about a presentation being "accessible," for example, meaning that the content of the presentation was easy to comprehend or perhaps that the listener meant he or she could identify with the speaker's points. 

According to the Merriam-Webster Online Dictionary, the term access can be defined as "permission, liberty, or ability to enter, approach, communicate with, or pass to and from," while the related term accessible is given a definition which includes "capable of being used or seen." These basic definitions are useful for building an understanding of the term accessibility as is relates to people with disabilities, and specifically to the concept of what we call "math accessibility."

Accessibility and civil rights

Many times, the terms "accessible" and "accessibility" are used in the discussion of civil rights for people with disabilities. Initially these terms were used to define the ability of people with physical disabilities who use wheelchairs to enter and navigate within a building. Thus, a structure was considered to be "accessible" when it had certain design features allowing unrestricted access for someone using a wheelchair, such as ramps and elevators.

Of course, opinions on what accessibility really means in practice can differ from one person to the next. So one of the first attempts to define accessibility--at least as far as buildings are concerned--was begun in 1959 by the President's Committee on Employment of the Physically Handicapped, which commissioned the creation of the first national accessibility standard by the American National Standards Institute (ANSI), a private standard-setting body. The resulting standard, ANSI A117.1, was first published in 1961 and quickly became cited as a mandatory requirement through reference in State and Federal law.

Federal accessibility standards

In addition to the ANSI standard, the Federal government later invested itself with the power to create uniform building accessibility standards in 1968 with the passage of the Architectural Barriers Act. Congress passed this Act "to insure that certain buildings financed with Federal funds are so designed and constructed as to be accessible to the physically handicapped." This legislation authorized the executive branch "to prescribe such standards for the design, construction, and alteration of buildings...subject to this Act as may be necessary to insure that physically handicapped persons will have ready access to, and use of such buildings." These standards, and many other accessibility standards mandated by the Federal government since that time, are now published under the authority of the United States Access Board.

It is vital to understand that, just as buildings can be made accessible or inaccessible by the inclusion or exclusion of certain design principles, this same concept of accessibility has been applied to the communication of information. For instance, under Federal law, all televisions produced in the US after July 1993 which are 13 inches or larger are required to have built-in closed-caption decoders for the hearing impaired. This way, audio information which is inaccessible to someone who cannot hear, can be made accessible through this technological design feature.

The concept of information accessibility in computer environments has more recently become a critical area of access for people with disabilities. To deal with the need for accessibility on the Internet, the World Wide Web Consortium (W3C) initiated the Web Accessibility Initiative and released a recommendation called the Web Content Accessibility Guidelines in 1999. Not long thereafter, the Federal government released its own set of Electronic and Information Technology Standards through the Access Board as part of the regulations enforcing Section 508 of the Rehabilitation Act. These standards set baseline access criteria for web pages produced by the federal government, and also provided accessibility standards for technologies such as computer software, fax machines, and office copiers.

Comparable access to math content

One of the fundamental principles of information accessibility is expressed in the language of the Section 508 statute: that individuals with disabilities must "have access to and use of information and data that is comparable to the access to and use of the information and data by such members of the public who are not individuals with disabilities." Comparable access to and use of information in electronic formats has been understood to mean that individuals with disabilities who use assistive technologies such as screen enlargement, synthetic speech, or speech dictation will be able to effectively utilize and benefit from these electronic formats on par with the way that people without disabilities use standard computer displays, keyboards and mice.

The concept of accessibility to mathematical information must also be understood within the framework of comparable access. Although basic mathematical information can be expressed using the alphanumeric characters found on the common computer keyboard, one does not have to go very far in complexity of math to run into problems. The common usage of elements such as superscripts and square root symbols, for instance, will typically be inaccessible to a blind person using synthetic speech unless this information is properly imbedded in the digital content to provide for accessibility.

The problem of math images and lack of comparable access

The current lack of comparable access to math occurs because the equations found in electronic information such as in computer software or on a web page are typically created using graphical image files, or digital pictures, of math equations. Images such as this can only be viewed and interpreted with human eyes, so that people who depend upon computer technology to synthetically read out loud the information on the screen will be unable to access these mathematical expressions. Thus, in this case, individuals who are blind, have a significant learning disability affecting reading, or have any other type of disability requiring them to use screen reading technology will have absolutely no access to this information.

One of the stopgap measures sometimes used to provide a degree of access to mathematical information is to include "alternative text" for graphics of math equations. In this case, the producer of the electronic format containing a math equation as a graphical image file will also provide a literary expression of the equation as a person might read it in his or her native tongue. While this does meet the baseline accessibility standard for access to common types of graphical information, this practice does not result in a level of access which is truly comparable to that of a person without a disability, who can view the equation in a two-dimensional form on the screen and interpret its proper meaning. Although this technique does provide a person with a disability some information that can be accessed with assistive technology, it is clearly inferior to the level of access that the non-disabled person would have through standard means, and therefore falls short of the legislative intent of Section 508 for comparable access.

Moving from accessibility to universal design

More recently, the accessibility community has adopted a standards-based approach to math accessibility using Mathematical Markup Language, or MathML, which goes much further toward true comparable access to math. MathML is an XML application for describing mathematical notation and capturing both its structure and content. Using MathML enables mathematics to be served, received, and processed in digital environments such as the World Wide Web, just as HTML has enabled this functionality for literary text. Furthermore, using MathML provides for a standard approach to content tagging and information structure which can make mathematical information available to assistive technology in a way that is comparable to standard visual access.

One of the most important aspects of using MathML, however, is that it provides the capability to move beyond considerations of accessibility as an "add on" or "alternative" approach to creating universally designed math content, which has benefits for all learners--not just students with disabilities. The term "universal design" means "a concept or philosophy for designing and delivering products and services that are usable by people with the widest possible range of functional capabilities, which include products and services that are directly accessible (without requiring assistive technologies) and products and services that are interoperable with assistive technologies." When MathML is used to author digital math materials, the resulting content can be universally used by all people. Math materials created using MathML can be transparently rendered in many ways depending upon the user's needs. It can be displayed on a computer screen, printed on paper, enlarged, spoken by synthetic speech computer applications or made into braille.

MathML benefits all users

Using MathML provides not only comparable access to math content for students with disabilities, but gives all students access to rich math content with support for enhanced learning delivery modes. Equations authored in MathML can be displayed onscreen with highlighting that moves in sync with synthetic speech, providing students with multi-modal visual and aural learning support. MathML also provides the capacity to allow students to visually and aurally "walk through" various parts of an extended equation at their own pace. These capabilities will aid all students as they learn math concepts.

So, to go back to our Webster definition of the term accessible, with MathML, math can truly be made "capable of being used or seen" by all people--even by those who cannot "see" in the traditional sense of the word, but who depend upon assistive technology to access information. And just as physical structures are made accessible by the inclusion of standardized design features, documents containing mathematical information can now be made accessible by using MathML, a standardized digital design feature providing unrestricted comparable access to math for people with--and without--disabilities. Finally, the universal design features of math content authored with MathML will provide enhanced learning benefits to all students. 

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