Field Penetration of Shielding Barriers, Low Frequency Effects

I t is commonplace among e le c t r o m a g n e t ic s h i e l d i n g e n g in e e r s t h a t low f re q u e n c y m agnet ic s h i e l d i n g p r e ­ se n ts un ique prob lem s. I t may be g e n e r a l l y s t a t e d t h a t , f o r c e r t a i n mid f r e q u e n c i e s , s h i e l d i n g is w e l l unders tood an d , a t v e ry h igh f r e q u e n c i e s , a n o th e r un ique s e t o f problems o c c u r . In t h i s s h o r t p a p e r , I w i l l address low f req uen cy and s t a t i c magnetic s h i e l d i n g .