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Web Accessibility in Europe

How People with Disabilities use the Web

Evaluation Methodology

Web Accessibility Validation Scheme and Quality Mark

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How People with Disabilities use the Web

Dislaimer

Please, read carefully the disclaimer before any use of this curriculum.

Overview

Introduction

Users with disabilities, and the elderly, may experience problems in accessing content on the World Wide Web. These problems however can be solved by using a series of assistive technologies. An assistive technology can be defined as any product, instrument, equipment or technical system used by a person with a disability, which prevents, compensates for, supervises, alleviates or neutralises the effects of the disability when accessing web content. Such assistive technologies facilitate processes of interaction and access to page content and also help to get the most out of the browser utilities used.

A web browser is a software application enabling the user to download, display and execute different types of documents from web servers throughout the world via the Internet: hypertext documents (HTML, XHTML, XML), graphics (JPG, PNG, GIF and others), video clips (WMA, AVI and others), sound (MIDI, MP3 and others), animations (Flash, SVG and others) and other various programmes (Java, JavaScript and others).

Today's browsers not only interpret web server content to display it correctly, but they also offer a wide range of options to tailor web content to the end user's preferences. In the case of persons with disabilities, the browser's adaptation capabilities will be a determining factor in gaining access to web content and therefore the careful selection of a browser and taking advantage of its technical possibilities will influence the final performance of the application.

For certain web users, the proper selection of browser software is not enough. This selection must be further supplemented by assistive technologies (screen readers, screen magnifiers, Braille display, voice recognition software, etc.) enabling these users to effectively access information retrieved by the browser.

Thanks to assistive technologies, persons with disabilities are able to process web content (providing that the latter is accessible) without their disability limiting access to information.

Objectives

The main objectives of this module are:

Contents

Persons with disabilities

The Disability Discrimination Act 1995 ([DDA]), an act by the UK parliament, defines disability in the following way:

A person has a disability if he or she has a physical or mental impairment that has a substantial and long-term adverse effect on his or her ability to carry out normal day-to-day activities.

There are five main groups of disabilities: visual, auditory, physical, language-related and cognitive / neuro-sensorial disabilities.

Visual Disabilities

Visual disabilities can range in intensity from colourblindness (difficulty in distinguishing colour) to impaired vision or total blindness.

Encountering difficulties in colour perception means that the eye does not respond to certain colours. For example, one may find it difficult to distinguish red from green or yellow from blue. For this reason, web content designers should not code content or include information which can only be identified via colour, e.g. denoting red fields in an application form as being compulsory.

A visually impaired person is one whose visual acuity, after treatment and/or correction, cannot be improved to a level that would normally be acceptable for reading without the need for a special level of light or the need for magnification. There are several types of visual impairments such as tunnel vision, loss of central vision, blurry vision and others. Visually impaired users typically use a screen magnifier to enlarge part of the screen, some of them prefer using a screen reader in addition. Similarly, they can also use the facility provided by some browsers to enlarge font size, providing that the developer of the web site in question used relative sizes for text on the page.

Blindness implies substantial and uncorrectable vision loss in both eyes. Blind users typically navigate the web using a screen reader ([WIKI-SCREENREADER]) which reads the content on the screen aloud to the user or passes the content on the screen to a braille display. For the screen reader to work effectively however, the content designer must have used proper formatting (for headers, lists, hyperlinks, etc.) and alternative text for graphical content.

Auditory Disabilities

There are a number of auditory disabilities ranging from mild hearing problems to partial or total deafness.

Mild hearing problems can be compensated for with sound amplification instruments.

Deafness is an auditory impediment whose severity prevents the processing of linguistic information through the sense of hearing, irregardless of the use of amplification equipment. In many cases, deaf persons encounter additional accessibility problems owing to a common deafness-related lack of command of language. These cases call for simple vocabulary, short sentences, outline descriptions (in the case of extensive bodies of information) and textual information supported by images, etc.

Persons with auditory impairments should not encounter many difficulties accessing information on the web. But as regards content, designers have to take into consideration equivalent alternatives for auditory content and ensure that texts are not too complex and therefore easy to read.

Physical Disabilities

There are a number of physical disabilities affecting different body parts such as: weakness, muscle control limitations (involuntary movements, lack of coordination or paralysis), numbness, joint problems and/or missing limbs.

Many web users with physical disabilities have problems undertaking certain physical activities such as moving a pointer, striking two keys at the same time or holding down a key on the keyboard. In more extreme cases, users may be unable to use a keyboard or mouse and therefore need an alternative data input system. Such a system would either be based on voice or on movements of other body parts (head or mouth) using alternative cursor movement systems such as a head wand or punch. Access to web content in this case involves total interaction with the keyboard.

In the case of voice-based data input systems, programmes use the labels associated with each element of the interface (e.g. buttons, links, dialogue boxes). To ensure effective interaction using voice, suche elements must be clearly labelled.

Language-related Disabilities

Speech impediments indicate difficulties in producing understandable language.

Associated with speech impediments is an impairment known as dyslalia. Users with dyslalia have problems articulating sounds characterised by an inability to pronounce words correctly. This can be due to a problem in the person's central nervous system problem or a physical abnormality of the articulatory organs.

Language-related disabilities usually do not cause serious web access problems because access to web content via voice is rather uncommon.

Cognitive and Neuro-sensorial Disabilities

Cognitive and sensorial disabilities include a range of limitations such as dyslexia, dyscalculia, attention span disorder, limited intelligence, limited memory, mental health problems, epilepsy, and others.

In order to avoid web content access problems in the case of users with cognitive disabilities, information systems should be devised enabling persons faced with these sorts of difficulties to use them efficiently. For this purpose, simple systems need to be developed and tested on persons with cognitive disabilities in order to detect possible comprehension problems.

Main assistive technologies

The concept of assistive technology

Assistive technologies are tools which enable a person with a disability to carry out the same tasks as a person without any type of disability. An example would be a hearing aid used by a person with an auditory disability to perceive sound information from the environment. A wheelchair is another assistive technology that a person with a back injury would use to gain mobility.

So, assistive technologies are special instruments or devices enabling the undertaking of different activities which would otherwise be impossible. In other words, they are elements which facilitate or help individuals to lead their lives as normal as possible by compensating the disability and transforming the environment with a view to favouring integration.

All assistive technologies should have the following characteristics:

Assistive technologies are classified according to "ISO 9999: Technical aids for persons with disabilities - Classification and terminology" ([ISO-9999]). This is an exhaustive classification of all of the assistive technologies which can be found in terms of personal protection and care, personal mobility aids, aids for entertainment purposes and others. This standard includes a section on "Aids for communication, information and signalling", paying special attention to access to computer applications and web content.

For more information on assistive technologies we refer to the Association for the Advancement of Assistive Technology in Europe ([AAATE]), the European Assistive Technology Information Network ([EASTIN]) and the Foundation for Assistive Technology ([FAST]).

Assistive Technologies for Web access

In the realm of information technology and especially access to web content, a series of assistive technologies is used to facilitate access for users with disabilities. Examples of these aids include: screen readers, speaking browsers, screen magnifiers, voice recognition programmes, adapted keyboards and other cursor movement and information input devices.

Screen readers

Screen readers are specialised software which enable blind users or those with severe vision impairment to use a computer. The software is used in combination with hardware (speakers, voice synthesizers, etc.) to interpret text and images appearing on the screen and transform them into voice.

All screen readers, regardless of the model and the user's operating system, work in a similar fashion. They enable the user to navigate the web and the various applications on the computer, via voice synthesis tools as the output device (sometimes also equipped with a Braille display) and the keyboard as the input device.

Some examples of screen readers are:

JAWS

JAWS ([JAWS]) is one of the most popular screen readers on the market today, providing access to software applications as well as the Internet. It also provides support for Braille devices and comes with an integrated voice synthesiser.

HAL

HAL ([HAL]) is a screen reader for use with any type of Windows application. It reads text and also recognises dialogue boxes, icons, etc. In addition, it works with most Braille devices.

Windows-Eyes

Windows-Eyes ([WINDOWS-EYES]) is an advanced screen reader programme. It is able to read all types of applications from websites and documents in PDF format, and is adaptable to any type of external synthesiser.

Gnopernicus

Gnopernicus ([GNOPERNICUS]) is a screen reader and screen magnifier enabling blind and visually impaired users to effectively use Gnome 2 desktop and Gnome/GTK +2.

Speaking Browsers

A speaking browser is software enabling blind or visually impaired users to browse through web content expressed in voice form. Speaking browsers are somewhat limited compared to screen readers as they do not guide the user in the use of the operating system and they lack advanced accessibility options such as the reading of complex tables, location of headers, lists, etc.

IBM Home Page Reader

IBM Home Page Reader ([HPR]) is a speaking browser developed by IBM. Home Page Reader reads the information on a webpage aloud, including conventional text, tables, graphic descriptions, fields and forms for the input of data, etc. Home Page Reader is compatible with Microsoft's Internet Explorer and voice recognition technology. Users access the programme using a standard keyboard, a numerical keyboard or a mouse and listen to the information on the webpage via a voice synthesiser.

Screen magnifiers

Screen magnifiers are software tools which considerably enlarge the size of information appearing on the screen thus facilitating access for visually impaired users. Additionally, they have the ability to adjust contrast, colour, font types and sizes.

A wide range of screen magnifiers is available on the market, each featuring different percentages of enlargement and some with voice synthesis support. There are also a multitude of applications enabling partial or total zoom options to suit the needs of the user.

Some of the most noteworthy screen magnifiers are as follows:

LunarPlus

LunarPlus ([LUNAR-PLUS]) is a screen magnifier equipped with voice synthesis.

Magic

Magic ([MAGIC]) enlarges screen content up to 16 times its original size and includes an optional screen reader. It is also equipped with a voice synthesiser making it possible to read any text appearing on the screen.

Zoomtext

Zoomtext ([ZOOMTEXT]) is a dual-use screen magnifier: enlargement (Level 1) and enlargement along with voice synthesis (Level 2). Voice synthesis is used to support the reading of menu documents and dialogue boxes. It facilitates compatibility with other assistive technologies such as JAWS (beginning with version 4.51).

Text-only browsers

A text-only browser enables the user to navigate through web content, displaying all information in text format (e.g. through disabling style sheets and displaying text alternatives instead of images).

Lynx

Lynx ([LYNX]) is the most popular text-only browser worldwide. It is freely distributed and can be downloaded automatically. It was originally developed for the Unix platform but today there are versions which work on other operating systems.

Voice recognisers

Voice recognisers are information input devices used by persons who have difficulties using a keyboard or mouse. The voice recogniser converts the user's voice into commands, which are sent to the operating system via a microphone, taking the place of mouse movements or keyboard strokes. The software has evolved quite a lot in recent years and now provides a large number of options. Voice detection has also improved and only requires a few short exercises prior to use. The supply of voice recognisers is limited. Below is a description of the most frequently used:

Dragon Naturally Speaking

Dragon Naturally Speaking ([DRAGON]) is a voice recogniser with a high voice to text conversion precision rate. Complex tasks can be conducted (activation of a link, sending of forms, etc.) with a simple word or phrase. It is also very flexible in converting recorded voice to text from digital recording devices such as the Pocket PC, Palm Tungsten and the Tablet PC.

IBM Via Voice

IBM Via Voice ([VIA-VOICE]) is a voice recogniser allowing for control of the operating system and applications via voice; it takes dictation in the word processor or note pad. It can also be used to surf the Internet or answer e-mail by means of voice commands. IBM ViaVoice requires full training and a user adaptation period to make voice recognition effective.

Braille display

A Braille display is a hardware device which, in combination with specific software, displays screen content in Braille characters, enabling blind and deafblind users to access information on the computer screen. The system interprets the words or graphics on the screen (similar to screen readers) and translates them in Braille. Braille displays offer some screen movement options and even command activation, although the input device is the conventional keyboard.

A number of Braille displays from various manufacturers are available: Alva, Braille Ex, Braille Focus, Braille Lite, Ecobraille, HandyTech, Power, Braille, Technibraille, Type Braille, etc.

Alternative web browsing methods

In today's society, computers have become a vital tool for work as well as for social life and entertainment. This has benefited people with disabilities by allowing them to take part in activities from which they were formerly excluded. At the same time, information technologies are also creating barriers, given that computers by default do not pay attention to user diversity.

In many cases, Internet surfers use a graphic browser with the majority of players or plug-ins installed and control the browser via the mouse and occasionally the keyboard. However, this is not the only possible scenario. Not all web users use the same devices to surf the Internet, nor do all users navigate in the same way ([BROWSING]).

Hands on a braille display Person working on the computer with a laser head mouse
Screen with screen magnifier running Person working on the computer with a mouth stick

Blind web users typically use a screen reader programme to access the information displayed in the browser. They listen to the textual content of web pages via voice synthesiser applications called screen readers or speaking browsers.

Visually impaired users normally use screen magnifiers to enlarge images or activate a larger font size available in their browser. They frequently disable the colours defined in web pages in order to get the maximum possible contrast between text and background.

Deaf or hearing impaired users do not perceive acoustic signals or the audio band of multimedia content. In the case of those who were born deaf, vocabulary may be relatively restricted, thus hindering the comprehension of excessively long texts or those with an abundance of new terms or complex syntax. Adapted subtitles and information embedded in images and diagrams are very useful for this type of user, as is the inclusion of videos in sign language.

Users with motor deficiencies, and elderly persons, encounter difficulties in handling certain cursor movement devices such as the mouse. Users affected by these deficiencies control the computer exclusively from the keyboard or special devices (head wands, buttons and others) using the accessibility aids provided by their operating system.

Users affected by mild cognitive difficulties may encounter problems in correctly interpreting symbolic language (the icons, for example) and may easily become disoriented when faced with a complex web navigation scheme. Simple vocabulary, simple syntax and the use of explanatory texts and category lists are all helpful in order to adequately comprehend texts.

Other users have slow Internet connections or may be using old browsers or do not have the latest players and plugins available. These users have difficulties accessing certain types of graphic information and undertaking tasks requiring scripts. The creation of alternative content should therefore be taken into consideration. There is also a growing number of users who access the web via personal assistants (PDAs) and mobile telephones with very small displays, thus limiting access to content as well.

Web developers should bear in mind the various characteristics of web users (how they use their computers and how they surf the Internet) when devising the best way to apply accessibility conditions to a website and to all projects undertaken with web technology. Similarly, they should envisage this variety of situations and construct sites which can be visited and used by any of these users.

Keyboard navigation

Website navigation via keyboard strokes is not extremely common, although there are people who prefer the keyboard over the mouse or, indeed, those who are unable to use the mouse for various reasons.

While navigation of web content seems to be the perfect medium for the mouse, there are a great many other options making keyboard navigation a possibility and which content developers should consider. Some important aspects to keep in mind are:

In addition to assistive technologies, the configuration and coding of a website to make it accessible via keystrokes makes browsing much easier for persons with disabilities.

Characteristics of the main web browsers

The browser is a programme which requests documents residing in remote servers throughout the entire Web and displays them on the screen. The browser needs to interact with the hardware and the software programmes installed on the computer.

Web browsers are typically offered free of charge and may be downloaded from manufacturers' websites. Below is a list of the main browsers, with their accessibility options mentioned in each case. For a detailed list on what common accessibility features are implemented natively (without third-party add-ons) we refer to Wikipedia ([WIKI-BOWSERACC]).

Internet Explorer

Of the web browsers operating under the Windows platform, the most popular and widely used is Microsoft's Internet Explorer ([IE]). The fact that it is the most widely used browser also makes it the target of assistive technology developments. The main assistive technologies on an international scale are developed for Windows as the operation system and for Internet Explorer as the browser.

Internet Explorer incorporates some accessibility aids enabling adaptation of web content to user preferences. Its most important accessibility options are as follows:

Netscape

During the early years of browser development, Netscape ([NETSCAPE]) established itself as a benchmark for other browsers. For many years it was the most widely used browser, until the integration of Internet Explorer within Windows 98. Netscape then created the Mozilla Foundation with a view to receiving contributions and improvements based on Netscape's open code.
The latest versions of Netscape uses the Mozilla Foundation code thus finalising the evolution of the initial application. Today, given that it shares the source code with Mozilla, web page interpretation is exactly the same.

Netscape's accessibility characteristics are as follows:

Mozilla Firefox

The Mozilla and Mozilla Firefox ([MOZILLA]) browsers have been developed by the Mozilla Foundation, which manages the open license of the Netscape code and contributions made to the organisation. While it started out basing development on Netscape 4.0, it ended up developing a totally new browser from scratch.

Mozilla Firefox is a web browser within the framework of the Mozilla project. The aim of Firefox is to develop a new browser for the Mozilla suite ensemble but also to develope a browser independent of the suite, which is smaller, faster and provides navigation with novel characteristics.

Version 1.5 was launched on 29 November 2005 with numerous improvements, such as support for the new SVG, CSS 2, CSS 3 and JavaScript 1.6 standards, progressive software updates, drag and drop reordering of tabs, greater security and improved user-friendliness and accessibility.

With regards to accessibility, Firefox 1.5 includes simpler browsing options for all users including visually and motor impaired users.

Opera

Opera ([OPERA]) is an Internet browser which was created in 1994 by a company called Opera Software. As of version 8.50, Opera is free software, previously having been shareware or adware and before version 5.0 was for paying customers only. Opera Browser is known for its speed, security, standards support (especially CSS), small size, international projection and constant updating.

Opera is a graphic browser with many accessibility functions ([OPERA-ACC]) and elevated configuration capacity, allowing for comfortable navigation for users with disabilities.

In the case of visually impaired users, Opera features:

In the case of users with motor disabilities, Opera features:

Amaya

Amaya ([AMAYA]) is a W3C combined tool composed of a web browser and a writer's tool. Any web page opened can be immediately edited. Pages can be viewed and generated in HTML and XHTML with CSS, MathML expressions and SVG drawings. This software is freely available for both Unix and Windows platforms.

Successive improvements have been made concerning accessibility options in the new versions of Amaya. Currently, most tasks can be undertaken with Amaya without using the mouse. Amaya's main accessibility characteristics ([AMAYA-ACC]) permit:

Self-evaluation

Question 1

In designing a website it is important to consider that:

  1. Visualisation should be similar in all browsers.
  2. Content and navigation are correctly visualised in any browser.
  3. Technologies used are supported by the majority of the browsers.
  4. All of the above.

Question 2

A screen reader is generally used in combination with:

  1. Earphones and a screen magnifier
  2. Hearing aid and keyboard
  3. Keyboard and voice synthesiser
  4. Text-only browser and voice synthesiser

Question 3

Voice recognisers are used to

  1. Input information and give commands to the computer
  2. Activate links and send forms
  3. Dictate texts in word processing programmes
  4. All of the above

Question 4

Proper labelling of images with alternative text is important for users of:

  1. Internet Explorer because it is the most widely used by blind users
  2. Any browser
  3. Lynx
  4. Home Page Reader

Question 5

Specific software to enlarge the size of web page content is:

  1. Windows Eyes
  2. ZoomText
  3. Lunar Plus
  4. Amaya

Question 6

What input device do blind persons use?

  1. Mouse
  2. Voice
  3. Keyboard
  4. All of the above

Question 7

Keyboard navigation is made easier with:

  1. OnKeyPress events
  2. Tab indices
  3. Rapid access keys
  4. All of the above

Question 8

Of the following software, which is a browser and also a writer's tool to generate web content?

  1. Mozilla Firefox
  2. Opera
  3. Amaya
  4. All of the above

Exercises

Select a set of web pages (preferably 5) at least one of which should have the Double-A accessibility logo (government administrations, associations, etc.) while the rest of the pages should, in principle, not be accessible.

Exercise 1

Evaluate the pages with Internet Explorer, Netscape, Mozilla Firefox and Opera.

Exercise 2

Download the latest version of the screen reader JAWS and run it with the Internet Explorer browser open.
Download Jaws (demo version 40 mins)

Annex

References

[AAATE]
Association for the Advancement of Assistive Technology in Europe
[AI-SQUARED]
Ai Squared
[AMAYA]
Amaya
[AMAYA-ACC]
Accessibility in Amaya
[BROWSING]
Alternative Web Browsing - a compilation written by WAI
[DDA]
Disability Discrimination Act 1995 (DDA)
[DRAGON]
Dragon Naturally Speaking
[DOLPHIN]
Dolphin
[EASTIN]
European Assistive Technology Information Network
[FAST]
Foundation for Assistive Technology
[FREEDOM-SCIENTIFIC]
Freedom Scientific
[GNOME-DEVELOP]
Gnome Developer Group
[GNOPERNICUS]
Gnopernicus
[GW-MICRO]
GW Micro, Inc.
[HAL]
HAL
[HPR]
IBM Home Page Reader
[IBM]
IBM
[IBM-ACC]
IBM Accessibility Centre
[IE]
Internet Explorer
[ISO-9999]
ISO 9999: Technical aids for persons with disabilities - Classification and terminology
[JAWS]
JAWS
[LUNAR-PLUS]
LunarPlus
[LYNX]
Lynx
[MAGIC]
Magic
[MOZILLA]
Mozilla
[MOZILLA-ACC]
Mozilla's Section 508 Compliance
[NETSCAPE]
Netscape
[NUANCE]
Nuance
[OPERA]
Opera
[OPERA-ACC]
Accessibility in Opera
[VIA-VOICE]
IBM Via Voice
[WIKI-BROWSERACC]
Comparison of the Accessibility features of web browsers
[WIKI-SCREENREADER]
Screenreader - definition in Wikipedia
[WINDOWS-EYES]
Windows Eyes
[ZOOMTEXT]
Zoomtext

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