Flexible intermediate bulk containers are being widely used. Much concern has been expressed regarding the electrostatic discharge hazards around flammable vapor/air mixtures and some very sensitive dust clouds. Methods were developed to analyze and test powders with FIBC materials to predict full scale electrostatic charging characteristics. Comparison with full scale FIBC operations shows very good correlation. Operations using FIBCs, including grounded versions are not recommended in flammable vapor environments. When dusty powders with low dust cloud ignition energies are used for FIBC systems, engineering analysis and testing is required to assure ESD safety.