Currently, many logistics operators operate in both domestic and foreign markets using various forms of transport organization. Choosing a corresponding technology and appropriate form of transport has an influence not only delivery time and costs, but also has an impact on the environment as a whole. There is a plethora of public research available in global literature discussing various ways of exploiting transport. On the other hand, there is a lack of complex studies detailing carbon emissions coming from transport activity. Specifically, where a theory of organic fuel combustion in the form of a chemical reaction with oxygen is considered. To fill this gap, we offer an innovative Emission Model of Industrial Sources (EMIS) method. This method makes it possible to determine the amount of CO2 emitted into the atmosphere during various transport methods. It also enables us to estimate, in terms of CO2 output, a threshold where transport of containers via combined mode becomes more favourable for the environment, than road transport. We ran a simulation of our algorithm to create boundary conditions. This let us prepare a regression function of CO2 emission, for intermodal and road transport as a function of various transport distances. The simulation results suggest that our approach may be used by supervisory institutions, which are responsible further developing and utilizing combined transport.