Background/Aim. The global rise of multidrug-resistant Klebsiella pneumoniae is a major challenge to healthcare systems, driving research into phage therapy as an alternative treatment. This study characterizes 9 novel bacteriophages, assessing their genomic safety, host range, and stability during jet nebulization. Methods. Phages were isolated from sewage samples by the overlay agar method, followed by characterization based on whole-genome sequencing. Phage titer stability was evaluated after jet nebulization to assess suitability for aerosol delivery. Results. The isolated phages differ in plaque morphology, host range, and genomic characteristics. Belonging to 8 distinct genera, all phages were confirmed as strictly lytic, lacking lysogeny-related genes, virulence factors, and antibiotic resistance genes. The host range varied from 2% to 42%, with Myovirus-like phages exhibiting the broadest spectrum. Virion stability during jet nebulization correlated with morphology. Siphovirus-like phages demonstrated infectious titer reductions of 0.67 and 1.03 log₁₀ PFU/mL, whereas a Myovirus-like phage showed a minimal decrease of 0.36 log₁₀ PFU/ mL. All tested phages maintained the titers sufficient for therapeutic application, confirming suitability for inhalation delivery. Conclusions. The isolated phages possess diverse genomic characteristics and collectively lyse 57 out of 96 tested clinical bacterial strains, demonstrating a broad host range. All isolates maintained the therapeutically effective titers during nebulization. This stability and the absence of known antibiotic resistance genes, virulence determinants, and lysogeny-related factors validate their applicability for inhalation therapy. Urban sewage is a rich source of phages against prevalent Klebsiella strains, highlighting the value of environmental surveillance for developing local therapeutic phage panels as a strategy against antimicrobial resistance. Grants/Fundings. This research was conducted as part of the bilateral Ukrainian-Latvian research project “Complete genome sequencing and analysis of bacteriophages isolated in Ukraine as a crucial step towards realizing their therapeutic potential” (Grant ID LV_UA/2025/5 & LV_UA/2026/5, Latvian Council of Science; 0125U003007, Ministry of Education and Science of Ukraine).