ABSTRACT. - Carbon monoxide in the urban areas from Cluj County. Carbon monoxide is mainly an anthropogenic pollutant and it is a result of incomplete combustion of fossil fuel. This study shows the seasonal variation of carbon monoxide levels in Cluj County urban areas, during six months in 2008 (since July till December). For this study, three different locations, from Cluj County, were selected: Cluj-Napoca, Turda and Huedin. In each of them, we chose city points with intense anthropic activities, and some reference points with a minor anthropic impact. In order to evaluate the diurnal variation of CO concentration, in situ determination were done for 8 hours a day (9,30-16,30 OVR respectively 8,30-15,30, OIR). The data show a slightly variation for the CO level from one area to other. In addition, there is no significant seasonal and diurnal variation for the CO level.
Key words: urban CO, urban agglomeration, diurnal variation