Bruker BioSpec 70/30 USR V2, Manual

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Laboratory Infrastructure and Interactions
28 Site Planning Information BioSpec 70/30 USR_2_V020
5.3 Interactions
The MR instrument and its surrounding may affect each other based on the following
interactions:
• magnetic interactions
• electromagnetic interactions
• building vibrations and impact noise
• room air and cooling systems
We distinguish
• Standard Specifications: Specifications for the MR instrument and the facility to be
compliant with regulatory standards. The compliance guarantees the safe operation of the
MR instrument. See chapter
Standards [
}
21] .
• Functional Specifications of the MR instrument : Compliance with the Functional
Specifications is necessary to maintain the Operational Qualification of the MR instrument
for example with regard to MR image quality. These specifications are usually more
stringent than the Standard Specifications.
The following sections outline the interactions and the Functional Specifications originating
thereof.
5.3.1 Magnetic interactions
5.3.1.1 Ferromagnetic mass
The quality of the magnetic field of the MR system is negatively influenced by ferromagnetic
materials located in the immediate vicinity of the magnet.
This interference is generally caused by magnetic building materials in the immediate vicinity
of the magnet. All ferromagnetic materials in the building structure must be considered, e.g.:
• Steel reinforcements in floors and walls
• Pipelines
• Structural steel and reinforcements
• Heating elements
• Steel doors and steel window frames
• Crane rails and hanging trolleys
• Sub-structures
Limit of ferromagnetic mass density:
If there are floors or walls in areas that lie within the area defined by the 0.5 mT stray field
strength, the ferromagnetic mass density must not exceed 50 kg/m
2
.