A simple method to determine the magnetic field generated by transmission lines is presented in this paper. The magnetic field calculation takes into account the mitigating effects of passive loops, including their optimal position in the line by applying genetic algorithms. Calculations results are validated by case reports published in the IEEE Transactions, software package for electromagnetic field analysis, and experimental data obtained from MITIGACION DE CAMPO MAGNETICO DE LINEAS DE TRANSMISION UTILIZANDO BUCLES PASIVOS Diego Raul CaDaviD DaviD alejanDRo RamiRez FReDDy lopeRa anDRes Felipe CoRRea