Powder Volume Resistivity
The test is performed at two controlled relative humidity conditions, an upper humidity of 50% and a lower humidity of 15%, in order to see the changes in resistivity as humidity falls. In pharmaceutical production many of the processes operate at low humidity. The resistivity value will determine whether a material is conductive, static dissipative or insulating. With the latter case, care must be taken during movement of the powder to minimise charge accumulation which could increase the risk from electrostatic spark discharges.