The fluctuations of magnetic fields are measured in all three axes using a fluxgate sensor in a frequency range extending from DC (0 Hz) to 1000 Hz. The sensor has a range of ±10 µT and a typical noise level of <10 pTRMS.
Vibration is measured in the floor of the magnetic room in a frequency range of 0.2 Hz to 5 kHz depending on the sensor used. The sensitivity of the vibration measuring instrument (sensor and FFT analyser) is 9.78 V/g and the resolution 0.000001 g.
Four to eight hours are needed to conduct a full survey. A report is provided containing results of the survey which include the largest fluctuations during the measurement period in the time domain and typical amplitude spectrum, in the case of magnetic fields in a frequency range of 0…1000 Hz and in the case of vibration in frequency ranges of 0…100 Hz and 10 Hz…5 kHz.
- An order for site survey is received 2 weeks in advance of the desired date (plus time required to obtain visas if applicable).
- Test equipment and personnel are available on the date desired.
- Where visas are required, the customer shall provide a letter requesting our support for submission with the application.
- A temporary import permit for the test equipment and its subsequent re-export can be obtained.
- The customer supplies documents and/or drawings showing the precise location of the MRI equipment.
- A representative of the customer conversant with the customer’s wishes is available on site.