I have a report with several sections. Many of these sections have a paragraph at the top that describes the purpose of the section, and these paragraphs are all styled with the ‘i’-in-a-circle (information) icon at the top left of the paragraph.
For the ‘alt’ attribute of this image, should I use “Information icon”, or “Report Section Description”? I am more incline to go with the first, and maybe use something else directly on the paragraph to more explicitly describe it, maybe a title attribute or something.
In your case I would go for a short tag that doesn’t describe the image. As a screen reader user I prefer alt tags that are short and to the point. I don’t really care what the icon looks like, what color it is, what it’s shape is etc, all I care about is that this is an informational icon so what follows is not data. If you need more detail about an image use the long description attribute. For example if you were displaying a chart I would want an alt tag of “chart of the last 10 stock market days”. The long description of the image could then be quite detailed, something like “On day one the market went up 200 points, on day two it went down by 100 points, on day three it fluctuated in a range of 300 points but closed about where it opened” etc.