There are currently no EU Directives or other guidance to member states which bear directly on either emissions or air quality objectives of PAH, however, the World Health Organization has examd. the issue of PAH health risk on a no. of occasions and has published Air Quality Guidelines in 1987 and again in 1999. In general, PAH contg. ≥5 rings are found predominantly in the particulate phase; those contg. 2 or 3 rings are almost entirely present in the vapor. These gaseous proportions of PAH are subject to long range transport making them a global environmental problem. This paper describes a new method for the detn. of the major gaseous forms of PAH expected to be present in the ambient air. The purpose of this work was to develop a rapid and sensitive method for the simultaneous detn. of these PAH species using sampling on graphitized C black with subsequent microwave energy thermal desorption and mass spectrometry detection. Data are presented from measurements which were conducted to establish the exptl. conditions and the assocd. equipment for the validation of the method. [on SciFinder(R)]