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© Gigahertz Solutions GmbH
It is generally accepted to use the highest reading in the room
for comparison with limit or recommended values.
To be on the safe side in this comparison you may multiply the
measurement by 4 and use the result as base value for the com-
parison. This is often done to make safe recommendations even
in case of readings on the low side despite still being within the
tolerance band. One has to consider, however, that this may also
lead to higher values than actually existent.
Special case:
Radar for aviation and navigation. Radar beams are
emitted by slowly rotating antennas. Therefore they are only
measurable and “audio-analysed” every few seconds for millisec-
onds. This necessitates a special approach:
Set ”Signal“ to ”peak“. After a couple of radar beam passes read
out the highest number displayed. Because of the slow repetition
rate of the display necessary for all other measurements, the
numbers will vary considerably and will only be displayed for a
very short period of time.
In most cases the measurement will be at the lower tolerance
band or in the extreme case even up to a factor of 10 too low.
Limiting values, recommendations and
precautions
The ”Standard der baubiologischen Messtechnik“ (Standard for
Building Biology Measurements), SBM 2008, classifies measure-
ments (per radio communication service), with a note of caution
”pulsed signals to be taken more seriously than continuous ones“,
as follows:
Building Biology Recommendations as per SBM-2015
Peak
meas-
urements
µW/m²
un-
conspicuous
moderately
conspicuous
very
conspicuous
extremely
conspicuous
< 0.1
0.1 - 10
10 - 1000
> 1000
© Baubiologie Maes / IBN
In fall 2008 the "Bund für Umwelt und Naturschutz Deutschland
e.V." (
BUND) (environmental NGO) recommended a limiting value
of
1 µW/m² even for outdoor situations.
The
Landessanitätsdirektion Salzburg (Austrian health authority)
proposed already in 2002 to lower the present
”Salzburger
Vorsorgewert“ (precautionary value) to 1 µW/m² for indoor situ-
ations.
Limiting values imposed by governments are mostly considerably
higher. There are indications of rethinking, though. The Internet
provides large collections of recommendations and data.
Identification of the sources of pollution
After determination of the total exposure the next step is to find
out where the radiation enters the examined room. As a first step
eliminate sources from within the same room (e.g. wireless rout-