There are even situations in which conflicting objectives occur between measures to avoid ignition hazards due to static electricity. In operations such as taking a sample from a reactor vessel containing a flammable solvent, discharging solids still moist with solvent from a centrifuge or removing product heel from a centrifuge, the question arises as to which material is the most suitable for the sampling device, scoops or spatulas to be used. The conflicting objectives arise, because, if a grounded conductive sampling device or scoop is used, when this approaches the product, brush discharges can emanate from the electrostatically charged insulating product. If, on the other hand, an insulating implement is used, brush discharges can originate from the surface of the implement concerned. The selection of the most suitable material depends ultimately on the probability of an explosive atmosphere and an incendive electrostatic discharge occurring simultaneously. An assessment of this probability in turn depends on numerous in dividual factors such as the conductivity of the liquid or the bulk material still moist with solvent, the effectiveness of the inert gas blanketing during the manual intervention, the vapour pressure(over-rich) of the solvent at the working temperature, etc.