The paper presents reasonable proposals to adjust certain provisions of the act regulating aspects of railway transportation of liquid cargoes, including petroleum products, in order to improve environmental protection. The relevance of the study is provided by the Decrees of the President of the Russian Federation "Strategy of Environmental Safety of the Russian Federation for the period up to 2025" [1] and "National Development Goals of the Russian Federation for the period up to 2030 and for the future up to 2036" [2], according to which one of the priorities of the policy of the Russian Federation is to reduce emissions of pollutants that have the most negative impact on the environment in cities and towns. The study objective is to develop and substantiate proposals for improving legislation in the field of rail transportation of petroleum products to reduce their negative impact on the environment. A specific task is to amend paragraph 30 of "Rules for transporting liquid cargo in bulk in tank cars and bunker–type cars for transporting petroleum bitumen", which regulates the process of cargo discharge, in order to minimize emissions of pollutants into the atmosphere (hereinafter referred to as the Rules)[3]. The study object is " Rules for transporting liquid cargo in bulk in tank cars and bunker–type cars for transporting petroleum bitumen ", a key document regulating the rail transportation of dangerous goods, in particular petroleum products. The environmental aspects of the Rules have been analyzed, especially the requirements regarding the stage of unloading goods. Study materials and methods. The following materials and methods are used in the work: - comparative legal analysis of the current version of the Rules and related regulations (for example, "Rules of Industrial Safety of oil and petroleum products warehouses"); - methods for calculating emissions. Approved methods of computational and experimental determination of emissions of pollutants into the atmosphere due to evaporation of petroleum products were used. - experimental data. To quantify the problem, the results of the author's assessment of emissions carried out at the current site of unloading petroleum products in Khabarovsk Territory were used. The scientific novelty lies in the argumentation of the need to amend the current regulatory act based on the results of scientific research on environmental protection from polluting effects during the transportation of petroleum products by rail. Practical significance - the author's technical solutions aimed at reducing emissions of pollutants into the atmosphere due to the evaporation of petroleum products from railway tanks during their unloading are proposed. Conclusions. It is found out that current Rules do not regulate the emission of petroleum vapors into the atmosphere through the open hatch of the tank during unloading, which creates a significant environmental problem. It has been experimentally confirmed that annual discharge emissions can reach tens of tons. As a solution, it is proposed to supplement paragraph 30 of the Rules with a requirement for the mandatory use of specialized technical means during discharge, ensuring the sealing of the tank boiler, vacuum protection and organized discharge of the vapor-air mixture. This measure will make it possible to legislate environmental requirements for the unloading process, stimulate the modernization of infrastructure and reduce the polluting burden on the environment.