Fortunately, grounded objects shield electric fields. NO electric fields are present outside properly grounded metal shields. Magnetic fields are created by moving electric charges and electrical currents. Unfortunately, it is extremely difficult to shield magnetic fields. Lightning, transmission lines, transformers, and motors, all produce very high magnetic fields.
Distance is the primary factor in reducing the strength of a magnetic field.
With the rapid increase in the number of computers and monitors, stray magnetic fields often cause monitor interference, which can be reduced by shielding. 50 cm from a radiation source. Most other countries, including the US, have no regulations governing ELF radiation. Research studies have shown that ELF radiation alters the function of nerve cells, changes the density and healing rate of bones, disturbs the balance of important hormones, changes the growth rate and drug sensitivity of cancer cells, modifies the immune system's ability to fight disease, and can alters the heart rate of test animals. While some epidemiologic studies suggest associations with cancer, others do not, and experimental studies have not yielded reproducible evidence of carcinogenic mechanisms.