# Customized Approach to Greenhouse Gas Emissions Calculations in Railway Freight Transport
## 4 Results and Discussion  
The aim of this article was to propose a fully customized approach to GHG emission calculations in RFT for the AI. Firstly, the requirements for the calculation of GHG emissions from RFT in the AI were identified using three-round semi-structured interviews with highly qualified and well-founded employees of a leading company in the AI operating on the Czech Republic market. As a result, it was found that the area of GHG emission calculations is essential for the company because the company strives to minimize negative logistic impacts on the environment and society. The company does not currently use any RFT emission calculators or other similar tools, as there is no suitable calculator available to meet company requirements or restrictive assumptions. Following this, available railway freight GHG emission calculators were identified and analyzed from the perspective of suitability for the AI using comparative content analysis. As a result, we can state that none of the analyzed GHG emission calculators in the field of RFT is suitable for the needs of GHG emission calculations in the AI because it does not meet all the identified assumptions based on the results of the three-round semi-structured interview. Finally, a fully customized approach to GHG emission calculations in RFT for the AI was proposed, applied, and verified in the form of an interpretative case study. The summary of results for the test calculation is presented in Table 2.  
The CO\({}_{2}\) emissions are presented in Table 2, according to the requirements of the company, as total GHG emissions, average GHG emissions per 1 km, average GHG emissions per 1 t, and average GHG emissions per 1 ton-kilometer. At the same time, the presented results are divided into emissions by origin (BO and FO) and by approach (WtT, Ttw, and WtW approach). The total CO\({}_{2}\) emissions of the test calculation calculated by the WtW approach are 5167.72 kg\({}_{\text{CO2e}}\). These CO\({}_{2}\) emissions consist of emissions calculated by the WtT approach (2908.88 kg\({}_{\text{CO2e}}\)) and Ttw approach (2258.83 kg\({}_{\text{CO2e}}\)). The overall results of the model calculation were compared with the results of the EcoTransIT emission calculator [71] and can be considered valid. If the input parameters change, the results also change in a reasonable manner. This proposed fully customized approach to GHG emission calculations in RFT can be used by all companies in the AI worldwide, because the company that was used in the interpretive case study has plants around the world and the proposed approach was also tested for shipments in individual plants. This study contains some limitations that are worth discussing. The first limitation is the processed theoretical background. The authors cannot guarantee the use of all available sources, but the processed theoretical background contains all the essential knowledge in the field and the basic axioms. At the same time, the existence of other available materials that were not used in the processed theoretical background cannot be ruled out. Another limitation is the area of identification of assumptions for the GHG emission calculations from RFT. These assumptions were identified and synthetized by using three-round semi-structured interviews. It cannot be completely ruled out that there may be a company in the AI that will have a specific requirement for GHG emission calculations that is not implemented in the proposed approach. On the other side, semi-structured interviews were conducted with highly qualified and well-founded employees of a company which is the leader in the AI Czech Republic market. These employees have sufficient experience across the entire AI to be able to define all requirements for GHG emission calculations. The last potential limitation may lie in the selection of available GHG emission calculators for analysis. Again, the existence of other GHG emission calculators than those analyzed cannot be ruled out.