The commercialization of natural gas in Brazil is carried out on a volumetric basis. To guarantee reliability of this quantity, it is of paramount importance to have metrological control of static pressure and temperature among other items. With a view to meeting this demand, the Brazilian Regulations defines the fixed interval for calibration, but it may be extended using historical data, without however specifying the statistical tool to be used in the study. In this dissertation, four statistical techniques widely published in literature have been selected to establish the interval of calibration for the temperature and static pressure transmitters in natural gas networks with ultrasonic meters. Sequentially, a tool to support the decision-making was used: modified SWOT analysis with a weighting for each indicator, to define the statistical tool with the greatest potential, suggesting the new calibration interval for the studied cases. The results show that by suitable SWOT matrix, the value of higher significance refers to the Poisson approach because this method achieved the best score, so the new calibration interval suggested for static pressure transmitters and temperature is 322 days for custody transfer, which confirms the change from 90 to 180 days, depending Joint Resolution No. 1/2013 ANP-Inmetro. In relation to operational measurement, which is not covered by this Resolution, this study suggests a calibration interval of 273 days for these transmitters.