As discussed in Part II, making computers and software more accessible is not the sole responsibility of application software vendors. Many aspects of computer access are best addressed by others, such as hardware vendors, operating system manufacturers, or third-party access product manufacturers. However, there are some components of accessibility that can only be addressed at the application software level.
To understand the role of application software manufacturers, it is important to examine the roles of all parties involved in making computers accessible.
Each party has its own unique role, and must work together to achieve computer accessibility:
As much as possible, the computer platform itself should be made directly accessible by people with disabilities. The computer "platform" is defined here as:
The hardware and operating system components may be produced by a single vendor or by separate companies. These components work together, however, to give the computer its basic operating characteristics and requirements. There are some accessibility features that can only be implemented at this level, and those that are will benefit all application software manufacturers by reducing the need to build these features over again in each application program. It is also of benefit to users in that there is a standard user interface and operating characteristics across programs.
In many cases, particularly for individuals with mild or moderate disabilities, slight changes in the hardware or operating systems can make the computers directly and completely accessible without any further modification. Once these modifications are incorporated into the design of the hardware or software there is little or no additional manufacturing cost. This type of accessibility is called "direct accessibility," since it allows individuals with disabilities to use the computers directly as they come "from the box." This is the most cost-effective type of accessibility, and the most desirable, since it allows individuals who have disabilities to access and use the computers in the same fashion as anyone else. It also allows them to access and use the computers as they find them in educational, employment, or public environments without having to bring along and install special access software or hardware in order to use them (which is often difficult or impossible in public and some other environments).
A second role for standard hardware and operating system manufacturers is to design the computer platform to facilitate the connection and use of special access tools (software and hardware) for individuals with more severe impairments where direct access is not possible (see next section).
Although direct accessibility of computers is by far the best situation, the type or severity of some impairments precludes the ability to use computers "off the shelf" (even if the computers have been designed to include as many direct access features as practical). In these cases, special interfaces, software programs, or other accessories are required in order to allow the individuals to access and use the computers. The role of third-party or "special access" manufacturers is to develop the special hardware and software tools, and to make them available to people who require them. As noted above, standard hardware and operating system manufacturers can greatly facilitate this process by designing their hardware and operating system platforms to be compatible with the connection and use of such special access tools.
While the use of special access products to access a computer is not as desirable as being able to directly access and use the computers, there is a need for and advantages to using third-party access products for some people, especially those with more severe disabilities. On one hand, individuals who have to rely on third-party access devices do not have the ability to just approach and use computers in libraries, laboratories, or employment situations. They must carry their special interfaces with them and be able to connect them to or load them onto these computers before they can use the computers. On the other hand, third-party products which are targeted toward a particular disability can sometimes provide more powerful and efficient interfaces than could be efficiently built into a standard hardware/operating system. It is also sometimes necessary to incorporate additional hardware into the interface (e.g., a dynamic braille display) which would be impractical to incorporate into a standard computers design. Third-party access products are therefore important components in system accessibility, and the only practical approach for some individuals with severe or multiple impairments.
Thus, both direct accessibility (wherever possible) and third-party access products (where built-in accessibility is not possible or is not efficient enough) are necessary to meet the broad range of needs of people with mild to severe disabilities.
The first two parties discussed (the standard platform manufacturers and the third-party special access manufacturers) can work together to overcome most of the access problems faced by people with disabilities. However, access to the computer and its operating system does not guarantee full access to application software, and running application programs is the only use of a computer for most people. Some aspects of the computer's behavior are completely in the control of the application software. Therefore, effective access to computers includes cooperation by the developers of application software. There are three general ways that manufacturers of application software can improve access to and usability of their programs.
Not all information needed to operate the program is available at the system level. Cooperation by the application program is therefore necessary in order for standard or special access features to be effective.
For example, most programs running on graphics operating system use the system tools to display their menus. Access features can thus be designed which attach themselves to the system tools and provide access to all of these menus. Occasionally, however, an application will create a custom menu or palette without using the standard system menu tools, or by using them for only part of the menu function. In this case, the special access features attached to the operating system would be unable to determine what the items in the special palette were in order to present them to the individual with the disability (e.g., if they were blind) and to allow the individual with a disability to choose from among them.
In some cases, the standard access features built into the operating system may allow the person with a disability to use a program, but only in some round-about or inefficient manner. A slight change or option in the application program could substantially increase the efficiency with which individuals with disabilities could operate the program. Since the person with a disability has to compete with their able-bodied colleagues, the ability to operate the program efficiently can be important to their maintaining comparative productivity to their colleagues.
For example, dialog boxes and many interactive programs may have numerous buttons in them. An individual who can tab between the various buttons and fields would have access to the dialog box. However, this type of operation would be much slower than that of other users, who could simply click on the desired buttons to access them rather than having to tab around. Having the ability to type a command key to activate any button directly would greatly increase the speed with which a person with a disability (and anyone else whose hands were on the keyboard) could access and use these programs.
Application programs can unknowingly include features which cause standard or third-party access features to break, or just not work with that program or function of the program. Understanding what accessibility features exist and how they function can help to prevent this problem. It also makes the program generally more robust and compatible with other nondisability-related third-party add-on programs.
For example, using nonstandard techniques to read the keyboard, write to the screen, or show a cursor may be done for performance or other reasons, but could circumvent or break access software. Several major application programs now do this.
In many cases they best means for providing access to persons with disabilities is through the use of third party access devices or software. However the design or improvements to a program can cause incompatibility problems for these third party access products leaving a person who depends on them without access to the computer or your software. Testing of your software for compatibility with access software and hardware can prevent this problem. Providing advance copies of the software to third party manufacturers for testing can also help avoid this problem if it is done early enough in the design cycle to allow for changes in the design to overcome incompatibilities
For example, screen reading software programs used by people who are blind can be made partially or completely ineffective depending on how new features, menubars, toolbars, etc., are implemented.
In addition to the three major players, there is sometimes a fourth player, the systems integrator, particularly in federal acquisitions. Since systems integrators do not usually create software or hardware, their role has not been well explored. However, for federal acquisitions, system integrators are often the individuals who select the hardware and software offered, and the individuals who provide the follow-up support. Their role in overall accessibility for offerings to the federal government is therefore substantial. Key areas where systems integrators can have a major effect are:
As previously discussed, the role of the systems integrator is not well understood, and points discussed here are therefore preliminary in nature. However, it is clear that the systems integrators will play a key role in determining the actual access that federal employees with disabilities will have to their computers and information processing environments. It is also clear that system integrators have major impact on which software packages are offered to the federal government for most of their packaged buys. Finally, it is clear that systems integrators cannot make the hardware and software in their packages more accessible or compatible with special access products from third-party vendors. They will have to rely upon selecting those hardware, operating system, and application software products which are most accessible and compatible with third-party access systems.
NOTE: These guidelines are directed toward the accessibility issues
as they relate to application software developers. There
is a separate document, titled Considerations in
the Design of Computers and
Operating Systems to Increase Their Accessibility to Persons with
Disabilities, which has been developed by and for hardware and
operating system manufacturers. At present, there is no document
tailored to the needs of systems integrators. Because of their
key role in federal acquisitions, and the fact that they face
different problems and questions in making the systems they offer
more accessible, a separate tailored document should be developed
to address their needs.
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