Chapter 15 509 environmental chamber to ensure constant humidity conditions. Figure 10 shows typical results for hair treated with a commercially available 2-in-1 shampoo and a conditioner. The ability for these products to mediate static buildup likely possesses a contribution from surface lubrication reducing frictional forces, but also the deposition of cationic surfactants is believed to increase surface conductivity. Figure 9. Static buildup measurement device (courtesy TRI-Princeton) Figure 10. Reduction of static buildup as a result of treatment with commercial 2-in-1 and conditioner products