Water Vapor Transport Through Protective Textiles at Low Temperatures

Abstract

This article surveys the physiological impact of waterproof textiles on the wearers of protective clothing. Wearer trials with test subjects in a climatic chamber involve ambient temperatures of +20. 0, and -20°C. The physiological function of breathable materials in comparison to a water vapor impermeable construction is quantified. Results show that water vapor permeable constructions offer a clear benefit to wearers at all tested temperatures: moisture accumulation in the breathable protective garments and in whole clothing systems are much smaller than in the nonbreathable one. Additionally, the ratio of evaporated sweat to produced sweat E/P is much higher for breathable constructions. Differences are statistically significant at levels of p > 0.995 or higher. There is no indication of a temperature dependency of the water vapor resistance of hydrophilic membrane laminates, but results show that. especially at ambient temperatures far below the freezing point. such breathable foul weather protective textiles still offer a great benefit to wearers.