Portable, inexpensive instruments to quantify stratum corneum hydration and skin erythema: applications to clothing science.

The level of stratum corneum hydration is assessed by measurement of the changes in skin resistance and is referred to as the galvanic skin response or electrical skin resistance. Skin erythema may be assessed by measurement of skin blood flow, tristimulus colorimetry or narrow-band reflectance spectroscopy. Currently available measuring devices are relatively expensive. Presented here are two inexpensive, hand-held, portable instruments which conveniently measure stratum corneum hydration and skin erythema.