Chapter 8 285 Figure 25 shows results from the exact same testing procedure to generate a Survival Probability plot describing breakage data for the conditioner-treated hair. Results now predict that around 5,000 grooming strokes (i.e. five times as many) are required to Figure 23. Weibull plot for repeated brushing data of virgin Caucasian hair at 60% RH Figure 24. Survival Probability plot for grooming virgin Caucasian hair at 60% RH