The frequency of these magnetic fields is typically 50/60 Hz. The MuFerro material is suitable for magnetic shielding in frequency ranges from 10 Hz to 100 kHz
MuFerro combines permeable and satiety characteristics which makes it extremely suitable for screening low-frequency magnetic fields.
Why use magnetic shielding/screening?
Magnetic fields pose a serious threat to human health and wellbeing. For instance, research has shown that exposure to magnetic fields of > 300nT or 0.003 Gauss significantly increases a person’s chances of developing leukemia. And there are numerous other physical symptoms associated with exposure to magnetic fields, e.g. headaches, depression, and insomnia. For this reason the Health and Safety Codes in many countries recommend that for working spaces exposure should be < 0.5 μT=500 nT and for public spaces it should be < 0.1 μT=100nT.
Apart from their negative impact on health, strong magnetic fields can cause interference or damage to electronics in the immediate vicinity of where the field is generated. Magnetic fields also interfere with sensitive measurements in hospitals and laboratories.
Holland Shielding Systems B.V. can implement magnetic shielding even after the transformer has been put into place. For screening entire buildings, or rooms, the shielding material is applied to walls, ceilings and/or floors. This protects both people and electronics.
Before the screening/shielding is ordered and installed, we can conduct a site survey (magnetic field strength measurement) for you. We not only measure the magnetic field strength but also locate its probable source. The measurement results are then presented in a report.
Example project 1
Due to space restrictions, one of our clients was forced to turn a room which had formerly been used for storage into an office space; this room was located on the floor above power transformers. However, powerful magnetic fields were noticed in that room which made the computer displays flicker, so we were asked to carry out a magnetic field measurement. It was found that the magnetic field strength was far above the standard referred to above – it was 750 nano Tesla. This magnetic field was reduced by the installation of an umbrella construction of MuFerro™ 6800. Since completion of this project, the magnetic field has been reduced to only 80 nano Tesla.
Example project 2
Below are some images of heavier transformer shields for military and medical applications where a very high reduction needed to be achieved.