Beta-Gauge for Hair Measurements

Abstract

THE quantitative measurement of hair is an important factor in studies of heat exchange between animal and environment. Methods currently employed consist in counting the number of hairs per unit area, measuring the mean hair length, and determining the weight of hair per unit area. In measurements of hair number or hair weight per unit area a major error arises from the difficulty of measuring precisely an area on the mobile, elastic, non-planar skin of an animal. Any method requiring the removal of the hair for measurement changes the heat-transfer characteristics of the area, and repeat measurements cannot be made on the same area. An absorption-type beta-ray gauge would appear to offer a solution to the problem of measurement of the mass of hair per unit area. It would be a rapid, non-destructive, and reasonably accurate direct measurement of the mass of hair per unit area at the point of measurement.