Size and shape of airborne dust from wood sanding II. Effect of sanding conditions on size and shape

To investigate effects of sanding conditions on sizes and shapes of airborn e dust particles, and relationships among the size and the shape indices, f ree falling particles during sanding of Japanese beech under various condit ions were collected on glass plates, Particle sizes, including Heywood diam eter, maximum length and maximum breadth, and particle shape indices, inclu ding circularity, slenderness ratio and area sufficiency were determined by an image analyzer. Coated abrasive grain size, sanding pressure, and sandi ng direction were the factors studied. The impact of various sanding factor s on the various particle sizes and shape indices were subjected to analyse s of variance, and relationships among sizes and shapes were analyzed by th e least squares method. The results were summarized as follows: (1) Coated abrasive grain size and sanding pressure influenced particle siz es and shapes during wood sanding but did not affect them after sanding. (2) Heywood diameter, maximum length and maximum breadth were highly correl ated with each other, and these sizes and circularity, and circularity and area sufficiency were also highly correlated, With increasing Heywood diame ter of the particles, maximum length, maximum breadth and area sufficiency increased, but circularity reduced. Slenderness ratio was not correlated wi th any of the size indices, circularity or area sufficiency.