The presented paper deals with the investigations on the content of chosen trace impurities in offal taken at various stages of technological process in felt production in hat industry, and its possible. The contents of lead, zinc, cadmium, iron, cobalt, copper, nickel and chromium in Bove hair washer wastes, in wastes from rinsing of washer, and in wastes from felting process were determined by spectrophotometric methods because of their simplicity and relative availability.

A procedure has been proposed for proceeding with homogeneous chemicals being technical products or reagents stored in unlabelled packages, in order to classify these substances to particular categories of wastes. A series of simple tests belonging to a classical analysis of chemical compounds, complemented with instrumental methods in needed cases has been proposed. The requirements have been established for equipment and necessary qualification of personnel in a laboratory in which identification is to be carried out. Attention has been drawn to risk accompanying this procedure and necessary precautions, which should be undertaken, especially due to possible explosive, inflammable and toxic properties of these substances. The worked out procedure was verified in tests and applied during cleaning the central chemical storage rooms.