Whose gas law is foundational in the technique of plethysmography?

The foundational gas law in the technique of plethysmography is Boyle's Law. This law states that, at constant temperature, the pressure and volume of a gas are inversely related. In other words, if the volume of a gas decreases, its pressure increases, and vice versa, provided the temperature remains constant.

In plethysmography, the measurement of lung volume relies on the principles outlined by Boyle's Law. During the procedure, changes in pressure within a closed system (such as the plethysmograph) can be measured as a subject breathes in and out. This enables the determination of lung volumes and capacities based on observed pressure changes.

In contrast, the other gas laws mentioned focus on different aspects of gas behavior. Charles' Law relates to the volume and temperature of a gas, Dalton's Law deals with the partial pressures of gases in a mixture, and Henry's Law pertains to the solubility of gases in liquids. While each of these laws is fundamental to understanding gas behavior in various contexts, it is Boyle's Law that is specifically applicable to the operation and interpretation of plethysmography.