The purpose of this part of IEC 60749 is to determine whether the marks on solid state semiconductor devices will remain legible when subjected to the application and removal of labels or the use of solvents and cleaning solutions commonly used during the removal of solder flux residue from the printed circuit board manufacturing process. This test is applicable for all package types. It is suitable for use in qualification and/or process monitor testing.. The test should be considered non-destructive. Electrical or mechanical rejects may be used for the purpose of this test. NOTE 1 This procedure does not apply to laser branded packages. Many available solvents that could be used are either not sufficiently active, too stringent, or even dangerous to humans when in direct contact or when fumes are inhaled. NOTE 2 The composition of solvents used in this standard, is considered typical and representative of the desired stringency as far as the usual coatings and markings are concerned.