Nuclear analytical techniques (NAT) have been used for first time to characterise fine particle in the city of Rijeka, Croatia. First set of 18 samples were obtained in the City centre between 24 February and 4 March 2012. Second set of 138 samples were obtained in area Luka Rijeka between 6 August 2013 and 28 February 2014. Samples were analysed in three laboratories: the Laboratory for elemental microanalysis (LEMA) Department of Physics in Rijeka by X-Ray Fluorescence (XRF technique), in the Laboratory for ion beam interactions (LIBI) Institut Ruđer Bošković in Zagreb, and in the Institute for Environmental Research Australian Nuclear Science and Technology Organisation (ANSTO) by Ion Beam Analysis (IBA). To check reliability of new XRF system in Rijeka, results of XRF analysis are compared with the results obtained by the well-established Institute at ANSTO. Very good agreement between techniques is obtained for all detected elements. After checking the results obtained by XRF technique, cooperation has been established with LIBI to increase the range of detected elements by using accelerator techniques. Concentrations of 18 elements from Si to Pb were obtained by XRF technique for both sets of aerosol samples. First set of samples was also analysed by IBA at ANSTO. Concentrations of 20 elements from H to Pb were obtained. Second set of aerosol samples was analysed by Proton Induced X-Ray Emission (PIXE technique) at LIBI. Concentrations of 22 elements from Na to Pb were obtained. The periods of haze with higher concentrations of S, K, Mn, Fe and Zn were analysed. Positive matrix factorization was applied to second set of data and 7 pollution sources were identified and their contributions to the total PM2.5 mass were determined. The major contributions to the fine fraction come from sulphates (34.5%), vehicles (21%), smoke (17.1%) and heavy oil combustion (10.8%).