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Multi-elemental analysis of samples containing uranium by Instrumental Neutron Activation Analysis (INAA) has been generally known as a problematic task due to the numerous radioisotopes produced from the uranium fission when the sample is irradiated with thermal neutrons. In k0 -standardized NAA (k0-NAA), it is possible to correct for this effect through the introduction of k0 -fission factors. In this work, the aim was to determine the feasibility of k0-NAA as a screening technique for accurate U and n(235 U)/n(238 U) isotopic ratio determination (we further refer to the technique as k0-UNAA) and where k0 -UNAA could be positioned versus the other screening techniques. In k0-UNAA, we use an adapted k0 formalism to determine the n(235 U)/n(238 U)-ratio. Several swipe samples spiked with different U isotopic ratios were analyzed and demonstrate the feasibility of k0-UNAA as a accurate and reliable screening method for the quantification of environmental samples up to several tens of ng. At these levels the uranium concentration can be quantified with a reasonable uncertainty and reliable n(235 U)/n(238 U) isotopic ratio analysis could also be performed.