Gloveboxes are frequently used for the protection of personnel and containment of an inert atmosphere within which operations upon pyrophoric or physiologically hazardous materials are performed. Leakage or diffusion of water vapor through gross leaks or through gloves may necessitate purification of the inert atmosphere. Since the required capacity of the purification system involves a summation of in leakage from all sources, quantitative information on the role of the glove as a contributing factor is of importance. This paper is intended to indicate the engineering application of an investigation into the role of the permeability of glove materials. Water vapor permeability through various glove materials has been determined mathematically as a function of film thickness, partial pressure of water vapor differential across the film, film surface area, and the permeability constants for a particular “compound.” Calculations indicate that a sample glove exposed to air at 75°F and 50% relative humidity on one surface and to a very low humidity on the other side will contribute 0.22 g of water vapor per day to a glovebox system (1). The same glove in use by an operator will contribute up to 2.8 g of water per day due to the increased partial pressure of water vapor differential between the two glove surfaces. These calculations allow the quantitative determination of water permeation through gloves and its effect upon the desired purity or operating dew point of a protective atmosphere system and its purification equipment.