Medical CAT-scanning: X-ray absorption coefficients,CT-numbers and their relation to wood density

Summary This paper describes how X-ray absorption coefficients and CT-number in medical CAT-scanning can be calculated for dry and wet wood. A comparison with earlier recorded data for dry wood showed that the deviation between calculated and measured CT-numbers was not significant. Linear regression showed that wood density could be measured with an accuracy of ±4 kg/m³. Wood having the same green density but containing different amounts of water have different absorption coefficients and CT-numbers. A linear relationship between CT-numbers and density of wood containing water was developed. Wood density could be measured with an accuracy of ±13.4 kg/m³.