About Web Accessibility

Introducing accessibility

The goal of web accessibility is to ensure that information or services delivered through websites are available to and usable by the widest possible audience. This requires that all users can:

• perceive and understand the information provided;
• perceive, understand and operate the website navigation;
• perceive, understand and operate the controls and inputs.

To achieve this, the design must take into account that the ability to see, hear, make inputs, read text or process information varies from user to user, across time and across situations of use. An accessible website will make provision for these variations.

Below are some examples of accessibility issues and techniques. Meeting recognised accessibility standards such as WCAG will make your website more usable for all these users.

Visual considerations

Visual impairment includes blindness, partial sight and colour blindness. Typical accessibility measures will include making sure that:

• text is resizable, i.e. users can use browser controls to increase the size of text they are reading;
• colours are carefully chosen, e.g. there is enough contrast between text and the background colour behind it to make it easily readable;
• images (and other multimedia items) have text descriptions, i.e. any information conveyed by the image is also available as text
• page layout is logical and easily navigable, e.g. Headings are used consistently to show the structure of the document. This means that users can use the features of screen reading software to learn the structure of a document or page, making it easier and faster to navigate through the information. (A screen reader is a software application that reads the content of a web page aloud in a synthesised voice to someone who cannot read or see the text on screen.)

Difficulty reading from screen

"I have to lean very close to see the screen. My eyes get very tired after using the screen for a couple of hours. Strictly speaking, I'm not supposed to work with a screen for more than 2-3 hours a day but sometimes you have to." - partially sighted user

Cognitive and learning considerations

Some users may have difficulty dealing with letters, words and numbers or understanding instructions, concepts and procedures.

"I know that a lot of people with dyslexia are put off the idea of even trying to learn about the web because of the necessity to read instructions." - IT training coordinator

One means of aiding such people is to maintain consistency between tasks and between visits to the website. This will benefit all users who, at times, may well be tired, stressed or in a hurry, all of which affect cognition. In addition, there are many, particularly older, users who use computers rarely and may find them intimidating simply because they are not familiar with them.

Language considerations

Many people find large blocks of text difficult to read on screen. This is especially true if the text uses complex language or industry or bureaucratic jargon. People whose first language is not the one being used on-screen, or who do not read very well, may find it particularly difficult.

Some 25% of the Irish population are "functionally illiterate". This means that they can read to some degree but would have difficulty reading a newspaper, filling in a form or following the instructions on a medicine bottle. To help these people, and all users, use the clearest and most simple language appropriate for a site's content.

This does not mean over-simplifying content on the website. The language used should be as simple as possible and presented in a clear and concise, easy to assimilate structure. References for online resources on writing for the web are contained in the "Further Information". section at the end of this document.

Hearing considerations

Users who are deaf or hard of hearing may have problems perceiving information presented as sound. These users' needs can be met by ensuring that all audible information is supplemented by a visual form such as transcripts.

A text transcript is a text equivalent for an audio track, including spoken words and other sounds such as sound effects. Subtitles are a text transcript of the audio component of a video track that is synchronised with that audio track.

Dexterity considerations

Some users have restricted movement or control of their arms, hands and fingers. This might be due to a medical condition, injury or old age. These users may have difficulty in controlling a mouse accurately enough to point to small buttons on screen. If they are unable to use a mouse at all, they may rely on keyboard control.

"I use the keyboard with one hand. I can't use a mouse." - Web user

Control difficulties

Many users find standard controls difficult to use. This image shows a person using two hands to operate a standard mouse.

To enable users with reduced dexterity to use a website, it must be possible to use the keyboard instead of a mouse to achieve all important actions.

This includes being able to move logically through the elements of a page, and being able to activate all objects and functions using the keyboard. It should also be possible to use the tab key to move logically through the elements of a page, especially in online forms.

Some users use Assistive Technologies to control Information and Communication Technology equipment and access websites. Examples of Assistive Technologies include wands attached to the head to press keys, sip and puff switches controlled by breathing, and special interfaces that are controlled by the user's eye movements or by voice recognition.

Technology considerations

Many users access the web using older computers, operating systems and browsers over slow connections.

"We use old machines in our office. The older machines struggle to keep up with the workload." - office worker

Users with impairments often use Assistive Technologies such as screen readers, screen magnifiers and special keyboards, which enable them to provide inputs and perceive outputs. Older browsers or Assistive Technologies do not support some types of content, so users may not be able to run the latest plug-ins and other advanced software. Websites that rely on proprietary software or features that are not widely supported by web browsers may be inaccessible to many users.

Examples of Assistive Technologies

• Head wand: a person who cannot move their hands might use a head wand for typing
• Oversized trackball mouse: Someone with a motor disability may find this easier to use than a standard mouse;
• Sip and puff switch: a person can use special software to control a computer by breathing in and out.

Not all users operate their computer with a mouse.