Abstract: A system for at least partially preventing passage an intrusive electromagnetic field into an internal volume of a structure is provided. The system includes a plurality of shielding modules positionable adjacent one another on an exterior surface of the structure for covering at least a portion of the exterior surface. Each of the shielding modules including a sensor and a shielding coil positioned around the sensor. The sensor is configured to measure the intrusive electromagnetic field and generate a signal based on the measured field. The system further includes a control unit in communication with each of the shielding modules, the control unit controls supply of response currents to the coil based on the signal such that the coil radiates a counteracting electromagnetic field that at least partially prevents passage of the intrusive field into the internal volume of the structure.