This document specifies a method of test for the determination of polychlorinated terphenyls (PCT) and polychlorinated benzyl toluenes (PCBT) in petroleum products and related materials by means of a specified gas chromatographic separation procedure. Following the gas chromatographic separation, quantification procedures are described for PCT Aroclor 5442, PCT Aroclor 5460 and PCBT (Ugilec 141).This document is applicable to unused, used and treated (e.g. dechlorinated) petroleum products including synthetic lubricating oils, to petroleum products and synthetic lubricating oils suitably recovered from other materials (e.g. from waste materials) and to mixtures of vegetable oils.NOTE 1This document has been developed as an extension of EN 12766 Parts 1 and 2 to provide a method of determining the total PCB content in accordance with Articles 2, 3 and 4 of EC Directive 96/59/EC [1]. The total PCB content is calculated by summation of PCB content, determined according to EN 12766-2, and PCTs and PCBTs according to this document.The three classes of materials measured in this standard can be quantified if they occur at concentrations greater than given in Table 1.Table 1 - Concentrations for quantificationClass of materialMinimumconcentrationMethod appliedPCB, polychlorinated biphenyls8 mg / kg(EN 12766-2 - Method A)4 mg / kg(EN 12766-2 - Method B)PCT10 mg / kg(EN 12766-3)PCBT5 mg / kg(EN 12766-3)Total PCB and related products a25 mg / kg(EN 12766-2 and EN 12766-3)a This value is only a best estimate. Real field conditions may, depending on the concentrations in the three different classes, result in other, more limited or more improved application ranges. It is the user's responsibility to demonstrate that the analysis has been performed in a valid calibrated concentration range.