How much information actually needs to be in the text equivalent? 

The text information associated with a non text element should, when possible, communicate 

the same information as its associated element. For example, when an image indicates an 

action, the action must be described in the text. The types of non text elements requiring actual 

text descriptions are limited to those elements that provide information required for 

comprehension of content or those used to facilitate navigation. Web page authors often utilize 

transparent graphics for spacing. Adding a text description to these elements will produce 

unnecessary clutter for users of screen readers. For such graphics, an empty ALT attribute is 

useful. 

Example of source code:  

What is meant by the term, non text element? 

A non text element is an image, graphic, audio clip, or other feature that conveys meaning 

through a picture or sound. Examples include buttons, check boxes, pictures and embedded or 

streaming audio or video. 

HTML Source Code:  

http://www.access board.gov/

How should audio presentations be treated? 

This provision requires that when audio presentations are available on a multimedia web page, 

the audio portion must be captioned. Audio is a non textual element, so a text equivalent of the 

audio must be provided if the audio is part of a multimedia presentation, Multimedia includes 

both audio and video. If the presentation is audio only, a text transcript would meet this 

requirement.  

What are ways of assigning text to elements? 

There are several ways of providing textual information so that it can be recognized by assistive 

technology devices. For instance, the  tag can accept an "alt" attribute that will enable a 

web designer to include text that describes the picture directly in the  tag. 

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