Filter element spark discharge is a recognized cause of fluid degradation in hydraulic and lube oil systems creating soluble by-products and sub-micron carbon particles that deplete additives, cause fluid darkening and lead to varnish deposits. Oil formulation changes from Group I base stocks to Group II-III base stock oils has yielded fluids with reduced conductivity characteristics which enhance the effects of element sparking especially during cold start conditions. Hy-Pro NSD (Non Spark Discharge) elements prevent one of the primary causes of thermal fluid degradation and is an important part of varnish deposit formation and phosphate ester fluid maintenance.