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

FIBCs are essentially big bags used for the transport and storage of intermediate quantities of powder product. Made traditionally of woven polypropylene, they hold from around 300 kg to 1000 kg of material in a shape which is approximately cubic, are fitted with filling chute, emptying cone and chute and are usually stacked on pallets or lifted by 4 loop straps at each bag corner. For many companies, FIBCs provide a very convenient way of handling medium quantities of powder which otherwise would require many drums or small bags. Their use is now widespread and they are to be found in many industry sectors including chemicals, fine chemicals, agrochemicals, food stuffs and others besides. Unfortunately the extensive use of FIBCs has lead to a significant number of fires and explosions which are directly attributable to electrostatic activity in the normal use of these bags. A lot of work has subsequently been performed both to understand the hazard and to produce bags which are safer to use than the first all-polypropylene bags. This paper reviews the electrostatic hazards associated with the use of FIBCs.