This Standard specifies a method for the determination of tetra-through octachlorodibenzo-p-dioxins, tetra-through octachlorodibenzofurans and dioxin-like PCBs in flue gas which are generated by combustion and chemical reactions, and discharged to a flue, stack or duct (hereafter referred to as duct) in stationary source emissions using a gas chromatograph/mass spectrometer (hereafter referred to as GC-MS). The GC-MS employed in this Standard shall be the double-focusing mass spectrometer (hereafter referred to as MS) where the capillary column of a gas chromatograph (hereafter referred to as GC) is used and its resolution is 10 000 or more.