Environment and Site Survey Measurement
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7.1.3 Measuring Floor Vibrations
Bruker  offers  a  service  for  measuring  floor  vibrations  using  specialized  hardware  and  soft-
ware.  We  recommend  measurements  to  be  done  over  a  period  of  at  least  1  hour  (ideally
much longer) to try capturing both steady state conditions and transient events.
For an accurate assessment of the floor vibration threshold, an FFT with at least 1601 lines
on 200 Hz bandwidth should be used. The Power Spectrum Display (PSD) representation is
depreciated for its limited accuracy in amplitudes.
Also  we  recommend  simultaneous  measurements  (multiple  transducers)  along  the  3  axis
(vertical, 2 horizontal).
7.1.4 Floor Vibration Guidelines: Bruker EMI Damping System
EMI damping system (Elastomeric Isolators)
Figure7.2: Threshold Values of Floor Acceleration: Tolerance Level for EMI Dampers
Frequency Maximum Velocity in Verti-
cal Direction
Maximum Velocity in Hori-
zontal Direction
1-10 Hz 1.6…0.64 µm/s 1.6…0.64 µm/s
10-20 Hz 0.64…6.4 µm/s 0.64…6.4 µms
>20 Hz 6.4 µm/s 6.4 µm/s
Table7.2: EMI Damping System (Elastomeric Isolators)