two-double fold test

What is two-double fold test?

two-double fold test meaning in Information Science terminology / glossary / dictionary is:

A simple trial used by conservators to detect brittle paper. One corner of a leaf is gently folded diagonally forward and back twice about one-half inch in from the point where the edges meet. Paper is found to be brittle if the corner breaks off or detaches with a slight pull after the fourth fold.

 

reference: ABC-CLIO