The Effect of Adhesive Film Thickness on the Sampling Efficiency of the Konimeter

Abstract

A technic of preparing adhesive films on konimeter slides from a soln. of petroleum jelly in xylene was tested and found to give results of excellent reproducibility and uniformity and is superior to the method in which glycerine jelly is applied with a finger. The performance of the konimeter in sampling coal dust is influenced by the thickness of adhesive film on the slide. Thin films (about 0.25/a) as conventionally used, give an exaggerated fine particle count and low estimate of the number of large particles as a result of the shatter and the rebound of the latter on impact with the slide. Thicker films (about l[mu]) provide a cushioning effect which largely eliminates these errors.