Why are paper bags so strong and how can their tensile strength be determined? Gemeinschaft Papiersackindustrie e.V. (GemPSI) answers these questions in this explanatory video about the tear resistance of industrial paper sacks. The video informs about the different reasons for the tear resistance: from the length, structure and quality of the paper fiber to elements in the sack construction. In addition, it explains how the tensile strength is determined by means of the TEA (tensile energy absorption). The explanatory video is part of a four-episode series about the tear-resistance of industrial paper sacks by GemPSI.