When there are more than one chemical list in the document tree (1), one could merge them by clicking the Combine button (2) located within the Catgeory definition module (Figure 1). Combine categories window (3) with all available lists in the same document appears. Some or all lists of chemicals could be selected and then the chemicals to be combined by logically AND/OR (4) operators. Creating of the new category finishes with clicking on OK (5) (Figure 1).

Figure 1

After selection of the combination logic the software defines a new category including chemicals which answer the criteria of the defined category (1) (Figure 2).

If AND is selected - the new chemical list will include only these chemicals, which are common for the selected lists, e.g. in this case (Figure 2) there is no chemical which presents in both lists (Figure 1).

If OR is selected - the new chemical list will include all unique chemicals presented in the selected lists (i.e. if a chemical presents in two or more lists, it will appear only once in the combined list).

Figure 2