Periodically the environment at LPLAB is checked with the aim to monitor the situation of our working place. The chance is taken to also check for possible sources of electromagnetic interference, even if in general our instruments are not particularly sensitive to it.
The typical RF electromagnetic pollution measured at LPLAB in the range 100MHz to 3GHz is shown in figure 1. Violet symbols show the typical average background field indoor, which is slightly less than 0.6 V/m. The yellow symbols show the stronger peak of 1.4-1.5 V/m, which is measured outdoor in front of North-East windows. Any possible internal source of RF field was switched off before measuring.
The typical background ELF magnetic field in the range 13Hz to 1kHz is about 0.005 microTesla (0.05 mG), measured switching the current off in the entire laboratory. No variations from day to night have been detected. The ELF magnetic field in my working place is typically 0.007 microTesla (0.07 mG) when power supplies and monitors are switched on.
The VLF magnetic field in the range 1kHz to 75kHz is less than 1 nanoTesla (<0.01 mG).
The typical background ELF-VLF electric field in the range 40Hz to 50kHz is under 1 V/m, measured switching the current off in the entire laboratory. The ELF-VLF electric field in my working place is typically in the range 6 V/m to 1 V/m when the current is switched on and the electric devices, like computers and monitors, are normally operated. However it increases approaching the laboratory walls.
The acoustic pollution is quite high at LPLAB due to the noise produced by the workstations, emphasized by the small space, and the additional noise from the nearby streets. The Equivalent Continuous Sound Pressure Level Leq ranges from 36dB(A), due to the very annoying computer background, to about 45dB(A) when street noise adds.
The computer background increases to 47-51dB(A), an irritating level for a research place, when the door of the workstation room is left open, as shown by the instrument panel in fig.2 (left plot).
The typical indoor radioactivity at LPLAB is shown in fig. 3. As common practice, the pulse frequency measured by our Geiger-Muller counter is expressed with the Dose Equivalent per unit time produced by Cobalt-60 radiation with the same pulse frequency. The average indoor level is about 30% larger than the average outdoor level, likely due to the Radon gas coming from the subsoil. Measured level appears on the average in Italy.
