Can the effect be tested with EMF meters ?
No, you cannot test a "before" and "after" measurement on an EMF meter. There is no emf device on the market or in the world that will change, block, or alter electromagnetic fields. If any emf protection company tells you their device will do this, they are not telling the truth. The only way to block wireless radiation is using very physical, microwave shielding fabric which is sold in different forms. When it comes to emf protection technology, the best devices will support the body by reducing the biological stress associated with emf exposure.