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Building Biology Recommendations as per SBM-2008
Peak
measurements
µW/m²
un-
conspicuou
s
moderately
conspicuous
very
conspicuous
extremely
conspicuous
< 0.1
0.1 - 10
10 - 1000
> 1000
© Baubiologie Maes / IBN
In Autumn 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.
Note for users of cellular phones and WLAN: Even below the measurement range of the
meters, even the highly sensitive HF38B, a reliable communication is absolutely possible.
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. cordless phones, wireless routers, etc.) Once this is completed, the remaining
radiation will originate from outside. For remedial shielding it is important to identify
those areas of all walls (including doors, windows and window frames!), of ceiling and
floor, which are penetrated by the radiation.
To do this one should not stand in the centre of the room, measuring in all directions
from there, but monitor the permeable areas with the antenna (LogPer) directed and
positioned close to the wall/ceiling/floor. The reason for this is that the antenna lobe
widens with increasing frequency. In addition reflections and cancellations inside
rooms make it impossible to locate the
“leaks”
accurately. See the illustrating sketch
below!
