Calculate the mass of natural gas Mr contained in a limited section of the main pipeline (MP) when the emergency break with time-sensitive cut-offline of cranes, confining the accident area, is an important parameter in evaluating the loss of gas in the accident. In addition, fire, its heat output and burning time flame torch are estimated and forecasted by this parameter. However, existing techniques are not sufficiently detailed. And author has not found the methods of system calculation of this parameter in the current methodological and normative documents. Despite the apparent simplicity of the problem, the analysis showed that the parameter Mr depends primarily on the calculation of the average temperature of Tcp, medium pressure Pcp rely on specialized techniques, which, in turn, include more than two dozen parameters that characterize the state of a gas in terms of its transport and depressurization of the pipeline, and Zcp - compressibility factor for each emergency site, the length of the section of the pipeline L and the inner diameter of the pipe dBH. Calculations of other parameters recommended by the standard methods are complex, three-dimensional and routine, require access to specialized software products that are not available in the current engineering activity. It introduces uncertainty in the choice of the calculation scheme and is accompanied by the production of different calculation results. The rationale for this method of calculating the mass of natural gas Mr involved in maintaining a burning torch in case of emergency break MP, the subject of this article.