Анотація: (English) The article discusses the theoretical foundations and practical application of fiber-optic sensors (FOS) for detecting gas leaks and monitoring temperatures at industrial facilities. A comprehensive analysis of the operating principles of FOS, their classification, signal modulation methods, and distributed sensing is carried out. Particular attention is paid to their application in aggressive environments, including in the oil and gas, chemical, and energy industries. The advantages and limitations of the technology are presented, as well as the prospects for its development within the framework of industrial digitalization and the implementation of IoT solutions. Directions for further research, including intelligent signal analysis, increased selectivity, and standardization of application are considered separately.