Still have questions about fair use exception? Here are several more helpful guidelines to help you make the appropriate decision.
The general guideline is that authors or creators keep copyright at least 70 years after their death. If a work is of corporate authorship, the copyright lasts 95 years from publication or 120 years from creation, whichever expires first.
You ask what percentage of a work is okay within the fair use exception. The following table might help.
|Media||Fair Use Limits|
|Text||Up to 10% of the original work or 1,000 words, whichever is less|
|Poems||Up to 250 words but further limited to the following:-Three poems or portions of poems by one poet
-Five poems or portions of poems by different poets from a single anthology
|Music||Up to 10% of the original work or 30 seconds, whichever is less|
|Photos and Images||Up to five works per artist or photographer or up to 10% or 15 works of a collection, whichever is less|
|Database Information||Up to 10% or 2,500 fields or cell entries, whichever is less|
(Wherry, 2002, pp. 168-169)
Here are some excellent websites which maintain copyright regulations up to date
Dr. Kelly Campbell, Associate Dean of Information Services at Columbia Theological Seminary