Skip to main content
danhutah
danhutah
New Participant
April 6, 2018
Question

Use of Span Tags for Greek letters, Asterisks, Superscripts/Subscripts?

  • April 6, 2018
  • 1 reply
  • 2682 views

I use Adobe Acrobat DC Professional on Windows 1 and have some questions regarding Span and Subscript/Superscript tags. I was taught to apply a Span tag to any kind of Greek letter, mu, asterisk, etc. I would then drag the character under Span and then apply Actual Text (writing in the name of the symbol). I’ve recently discovered that regardless of this Span tag, the Acrobat reader recognizes the symbol and reads it correctly.

On the other hand, I typically put any Subscript or Superscript number/letter underneath a respective tag. I have not been able to have Adobe Acrobat read those values correctly.

Are there any common practices for applying these tags? Is there any reason to keep using the Span tag for Greek letter, mu, asterisk? What is the best approach to tagging Superscripts/Subscripts? Should we use a Span tag for the Superscripts/Subscripts?

Thanks for any help!

This topic has been closed for replies.

1 reply

raeben3
raeben3
Inspiring
April 12, 2018

Using a Span tag with actual text will ensure that the screen reader will read the content regardless of the screen reader preference settings.  Screen readers may have default settings that preclude the reading of punctuation . A user will probably need to change those settings if they want every dot and dash to be read.  Some readers are better in this regard than others. Deque has an interesting article on the subject.

There is considerable discussion about this. At this point, I have to say -- if you want to be absolutely sure the screen reader reads it, you should continue to use Span.  If it's primarily a Greek symbol you are concerned about, you could test on 3 different readers - Jaws, NVDA and Read Aloud.

I wouldn't rely on Read Aloud alone as it is not a screen reader that most people who rely on them on a daily basis would ever use.

    Bevi Chagnon - PubCom.com
    Bevi Chagnon - PubCom.com
    Brainiac
    April 12, 2018

    I think you've hit a transition area for the industry.

    Today, most common Unicode symbols are correctly voiced by screen readers without the need for a span tag and actual/alt text. Years ago we needed to do that, but not so much in the past few years.

    If it's a Greek math or science symbol, make sure to use the correct Unicode symbol for it, which is Micron Sign Unicode #0085 (called its codepoint).

    1. Refer to the Unicode charts at http://www.unicode.org/charts/ and scroll to the section lower on the page for Symbols to find the codepoints of the symbols you need to use in your InDesign layout. Write down their codepoints.
    2. Then, using InDesign's glyph chart, insert the Unicode symbol for it (easiest way is to type the codepoint into the search field at the top: type 0085 to quickly find the micron sign and then insert it into the layout).
    3. Export your PDF as usual.

    Common problems:

    • Using the Greek letter mu U+03BC instead of the science/math symbol U+0085. The Greek language letter is not the same as the science glyph.
    • Using a non-Unicode font, like the old TrueType Symbols font, or Wingdings, Webdings, Zapf Dingbats. Because these fonts don't use the Unicode character set, their characters are not recognized or are misinterpreted by screen readers. (Note, most of the glyphs on the old Symbols and Zapf Dingbats fonts have been incorporated into Unicode, so you can find Unicode versions of them on many of the OpenType/Unicode fonts you already have. Or your can purchase new OpenType/Unicode versions of Symbols STD and Zapf Dingbats STD from the major font houses.)
    • Using a glyph that isn't yet recognized by our screen readers. JAWS and NVDA have improved their recognition of the major STEM glyphs, but not all of them. That's their problem, not ours. As content creators, our job is to use the correct Unicode symbol; the assistive technologies' job is to build their software to recognize them. All of us are bound to meet the same accessibility standard for Unicode fonts/character set. But if you are using an obscure glyph, then the old Span Tag with Actual/Alt-text would fix the problem.
    • "Primitive" screen readers like Acrobat's Read Aloud or Apple's VoiceOver don't recognize much more than the basic alpha-numerics. Our shop does not worry about this category of screen reader and instead we encourage the manufacturers to meet the accessibility standards. Again, that's their failure, not ours.

    FYI, an old (but still useful) blog of mine talks about Unicode issues for InDesigners at https://www.pubcom.com/blog/2013_12-03/unicode-accessibility.html

    |    Bevi Chagnon   |  Designer, Trainer, & Technologist for Accessible Documents ||    PubCom |    Classes & Books for Accessible InDesign, PDFs & MS Office |
      Terms & ConditionsAccessibility statement
      Using the community Terms of use Privacy Cookie preferences Do not sell or share my personal information ad choicesAdChoices