Hair Breakage 286 produce a 0.5% likelihood of breakage in conditioned hair while approximately 25,000 strokes are necessary to induce a 1% chance of breakage. Obviously, grooming habits and practices differ immensely but if it is assumed that 10 grooming strokes are employed each time a consumer brushes their hair, and that three such grooming experiences are performed each day, then 1,000 grooming strokes would be performed in slightly over a month. Therefore, continuing with this assumption, and under these conditions, it may be concluded that use of a conditioner in the above study prolonged the generation of 500–750 broken fibers from around 1 month to 5 months. Still more impressively, the duration for generating 1,000– 1,500 broken fibers rises from 3.5 months to 25 months. Weibull analysis in the modeling of repeated grooming experiments: The inverse of a Survival Probability curve is a Failure Probability curve. That is, a 99% likelihood of a fiber surviving corresponds to a 1% chance of failure. Therefore, it becomes possible to create a model that describes the whole repeated grooming Figure 25. Survival Probability plot for brushing of virgin and conditioned Caucasian hair at 60% RH