Chapter 10 345 attained by setting a suitably long equilibration time, or by having the instrument monitor the rate of weight change and setting a threshold limit at which point equilibration is taken to have occurred before the instrument moves on to the next condition. As already mentioned, full equilibration at each condition is lengthy, and generation of adsorption and desorption isotherms represent a considerable amount of time. For this reason, there may be the temptation to cut corners in an attempt to speed up data generation. Figure 9. Schematic of DVS equipment (courtesy of Surface Measurement Systems) Figure 10. Typical DVS experiment to determine adsorption and desorption isotherms for water and hair