Electrostatics requirement for intermediate bulk containers intended for use in explosive atmospheres

Intermediate bulk containers (IBC) of 1 m3 in volume are often needed for storing flammable liquids. These containers should also be suitable for use in potentially explosive atmospheres of zone 1 without safety hazards being caused. In the past, such containers were exclusively made of metal. Some years ago special designs made of insulating plastic material instead of metal made their appearance on the market. However, inappropriate construction or use of these plastic containers may create hazards as a result of static electricity discharges. For this reason, the build-up and decay of electrostatic charges produced during filling, emptying, transportation as well as by rubbing have been studied on several container types. On the basis of the experimental results safety measures are proposed, which will ensure safe operation of the container with regard to static electricity discharges.