Анотація: (English) The article discusses environmental sustainability at the well testing stage, which is considered one of the most sensitive processes in the oil and gas industry. Based on an analysis of international standards, guidelines, and industry data, sources and types of impacts are summarized, including flaring and venting, water discharge, chemicals, and waste/spills. Practices for reducing these impacts are evaluated. It is shown that maximum effect can be achieved by combining in-line testing with multiphase flow meters, trapping and compression, integration into existing systems, product reinjection, and zero discharge of water. Highly efficient flare systems are also important, as well as transitioning to methane measurement and reporting (MRV) programs. Limitations are noted, and directions for future development are proposed.