Validation across already created Workbooks

Is there a way to copy Validation from one workbook to another.

The Validation is a simple text length min 0 - max 30.

Then a Stop Message displayed advising users they have entered to many characters and to modify their entry.

There are about a hundred such workbooks, whilst it would have been easier to set Validation when they we're created, this wasnt done (before my time) and is now causing me a headache. As the field on the system this is imported into can only handle 30 characters.

Thanks.