Conductivity of insulating materials is a key parameter to determine how accumulated charge will distribute across the spacecraft and how rapidly charge imbalance will dissipate. However, methods are often not applicable to situations encountered in spacecraft charging, conductivity is more appropriately measured for spacecraft charging applications as the decay of charge deposited on the surface of an insulator. These parameters determined from classical methods were used in design techniques to mitigating spacecraft charging effects may produce remarkable error. In this paper instrumentation for both classical and charge storage decay methods has been developed. Experiments were conducted by both methods on R4 Printed Circuit Board. The experiments are similar to results from Jet Propulsion Laboratory and Utah State University.