Climate change and air pollution have a direct impact on the performance and lifetime of insulating materials. In recent years, Mazandaran and Golestan provinces in Iran have witnessed a climate change and an increase in air pollu- tion. This problem increases outages and losses in transmission and overhead distribution network. Moreover, traditional and empirical methods have been used for insulation coordination in past decades. In this project, a specialized software was used for checking existing lines in Mazandaran and Golestan Regional Power. Insu- lation computations and isolation studies using MATLAB software were used to present solutions for transmission and overhead distribution networks. This spe- cialized software has the ability to calculate the required minimum air gap and the minimum creepage distance and the number of insulators with due atten- tion to regional pollution, overvoltage due to switching and lightning, and power frequency.
