Bruker BioSpec 70/30 USR V2, Manual

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Laboratory Infrastructure and Interactions
30 Site Planning Information BioSpec 70/30 USR_2_V020
Minimum distance [m] Mobile sources of magnetic disturbance
2 ferromagnetic objects < 250 kg
4 ferromagnetic objects < 500 kg
6 ferromagnetic objects < 5000 kg
9 ferromagnetic objects > 5000 kg
40 subways, trucks, trains
Table 5.1: Limit values of magnetic disturbances
5.3.1.3 Effect of MR system to other equipment
The stray field of the MR system can lead to sustained disturbance of sensitive equipment in
the vicinity of the system and to irreversible damage.
The following table gives threshold values on acceptable disturbance of some equipment.
Before using equipment in the stray field of the magnet, check the acceptable fields in the
manual or consult the manufacturer of the equipment.
Disturbance
level (mT)
Equipment and systems
5 MR system electronics
3 Electric motors, cameras, mechanical clocks
1 Hard drives and mobile data media, credit cards, oscilloscopes
0.5 Medical implants, pacemakers, insulin pumps, neurostimulators, X-ray
equipment
0.3 Ultrasound equipment, video cameras
0.2 CT scanners
0.1 CRT monitors, particle accelerators, electron microscopes, mass
spectrometers, EEG equipment
0.05 X-ray image intensifier, gamma cameras
Table 5.2: Interference fields of equipment
5.3.1.4 Remote magnetic effects
The magnetic field of the MR system interacts with ferromagnetic materials built into the
building. The interaction leads to magnetization of the ferromagnetic materials, which in turn
may lead to an unexpected higher local magnetic field strength at distant sites.
A check must therefore be made as to whether there are ferromagnetic structures at the
magnet's installation site, which may lead to the aforementioned effects at distant sites. If
such structures exist, these areas must be measured, labeled or shielded separately after the
magnet has been installed.
5.3.2 Electromagnetic interactions
In the event of faulty installation or incorrect operation of an MR system, electromagnetic
interference to other equipment in the vicinity of the MR system can occur.