Radioactive xenon isotopes are members of the fission product noble gases (FPNG) family and help in the identification of production mechanisms and their extent in any nuclear installation. Therefore, it is necessary to assess the FPNG concentration in the air during the operation of any nuclear power plant. Presently, the available methodology of assessment of FPNG at almost all Nuclear Power plants worldwide (mostly light water-based) is through a computer-based gamma-ray spectrometry system. This method provides FPNG qualitative and quantitative identification through peak search within the acquired spectra of the collected air samples. For this purpose, the radioactive air sample from the active air of the plant is collected by the direct grab sampling method, which has inherent disadvantages as the sample size should be large enough to collect a sample representative of the entire stream. Usually, the collected samples are then analyzed in a high-purity germanium detector (HPGe) as a part of the gamma-ray spectrometer. This paper presents details about an alternative novel method for collecting and analyzing FPNG. This method is developed to overcome the disadvantages of the traditional method. The sampling here is based on cryogenic adsorption of noble gases on activated charcoal, enabling pre-concentration and improved detection sensitivity. Hence, compared to the traditional grab sampling technique, this method enhances the radioactive air collection capacity, ultimately reducing the minimum detectable activity and improving the sensitivity of environmental monitoring.