[en] The low-background setup is constructed for the investigation of rare processes of nuclear decay and low-level radioactivity measurements. The installation is located in the undeground laboratory of the Institute for Nuclear Research, the Ukrainian Academy of Sciences, at the depth of 430 m in a salt mine. The preliminary measurements of the NaI (Tl) detector background were made. The setup enables to measure the radioactive contamination of materials for low-background instrumentations at specific activity up to 10^-15Cu/g and to make the search of double beta decay and other rare processes at competing-capable level