This study presents the influence that the projection gas has on the corrosion resistance of the TAFA 30T carbon steel coating produced by the company Praxair on a carbon steel substrate ASTM A36, which had a surface preparation by means of sandblasting obtaining an anchor profile of approximately 47 microns. Referring to the design of experiments, a Taguchi orthogonal model was proposed with three levels and four factors considering the main parametrization variables of the thermal arc spraying machine such as primary pressure, application distance, current and voltage, taking in mind that air and nitrogen were used as spray medium to atomize gases, in order to isolate the oxygen present in the environment to a greater extent and that is one of the causes of the oxidation of the particles at the time of application. To study the influence of the projection gas, sulfuric acid immersion tests were carried out with a concentration of 1 and 3% for 120 hours, gravimetric test of mass loss and morphological characterization by conventional optical microscopy (MOC), in order to determine the physical and morphological changes of the coating. The preparation of the samples for each of the tests was done by cutting sections of approximately 6mm2 and had a surface preparation by polishing with abrasive paper. As a general result, it was obtained that when performing applications with nitrogen, the properties of the TAFA 30T coating were improved, which obtained a tendency to decrease porosities and oxide inclusions present in the coating.