Static electricity hazards in the use of flexible intermediate bulk containers (FIBCs)

Flexible intermediate bulk containers (FIBCs), usually made of highly insulating polypropylene fabrics, are used in large numbers worldwide. Concerning electrostatic ignition hazards relating to the insulating fabric, precautions are to be taken in fire and explosion endangered areas. There are different ways to meet this challenge by modifying the FIBCs antistatically. Therefore, tests must be conducted to ensure that the provided measures reliably eliminate electrostatic hazards. Usually, such tests are run in full scale, making them very costly. In addition, the results are difficult to reproduce, as experience shows. A reliable and replicatable method has been found, which is corona charging of the FIBC to simulate the electrostatic charge build up by the bulk. This paper presents and discusses the test method and its results, especially in aspects of essential grounding.