When passing a stool it is unlikely that you will know the consistency of the stool. The “Bristol Stool Chart” classifies stools into seven types ranging from from hard, separate lumps (type 1) to watery diarrhea (type 7). If there is water content present in the stool then that water can eat into the bag and cause it to burst. Toilet paper in the bottom of the HyStool bag helps prevent direct contact between a moist stool and the bag, and reduces the chances of the bag bursting. HyStool is not suitable for cases involving diarrhea.