This part of ISO 105 specifies a method for determining the consumer relevant shade change of textiles, of all kinds, (excluding silk and wool) and in all forms, to domestic/commercial laundering procedures in which a bleach activator (oxygen bleaching system) is used. The colour fastness resulting from oxygen bleaching in this test provides an indication of the shade change behaviour observed after multiple domestic/commercial launderings. This part of ISO 105 is not applicable for the assessment of the dye staining of adjacent fabrics, where suitable methods are described in ISO 105-A04. This part of ISO 105 does not reflect the contribution of optical brighteners, which are present in some commercial washing products, to shade change. This part of ISO 105 specifies a procedure incorporating the use of ECE1) non-phosphate reference detergent, sodium perborate tetrahydrate, and the bleach activator tetra-acetylethylenediamine (TAED). An alternative test procedure using the AATCC 1993 zero phosphate reference detergent (without optical brightener), and incorporating sodium perborate monohydrate and the bleach activator sodium nonanoyloxybenzene sulphonate (SNOBS) is currently under development.