Preface to the lecture, 1



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2

 

  



 

static


ELF

static


ELF

LF

HF



0 Hz      (1 Hz -

 

0 Hz



(1 Hz-

(1 kHz- (1 MHz-

100 Hz)

   


100 Hz) 10 kHz)

 

10 MHz)



magnetic field

 

electric field



alternating elec-

[Gauss=10

-4

T]

 



[V/m

   


tromagnetic field

 

Fig. 1.1:    Discussion about limits



 

 

 



Limits for professional exposition (electronics engineers) and 

Limits for non-professional exposition (population in general) 

according to the Recommendation of IRPA/INIRC

Limits according to VDE 0848 / 1989 



Limits according to VDE 0848 / 1992

 

 experimentally determined threshold values of reactions of 



biological systems 

:

 



1

 

Increase of the activity of movement of birds 



2

 

deflection of divining-rods 



3

 

influence on the time of reaction of men 



4

 

conditional reflexes of fish without electrical organs 



5

 

conditional reflexes of fish with electrical organs 



6

 

conditional muscular reflexes of men 



taken from: 

:     H.L. Konig: Unsichtbare Umwelt (Wetterfuhligk.), 5. Aufl., Bild 111, S. 123

 

Verlag Moos & Partner Munchen, ISBN 3-89164-O58-7



:    Habiger u.a., EMV, Verlag Technik, Berlin 1992, S. 152


Introduction 

3

 



1.1 Discussion about limits

 

Whoever follows the public discussions concerning electro smog always sees two arguing 



parties, whose standpoints lie so far apart that they inevitably talk at cross purposes and 

there can be found no consensus.

 

On one side the "affected" find together who maintain to have found the electromagnetic 



radiation as the damaging cause for their problems. They are to be taken serious, even 

when only their personal sensitivity serves as means of measurement and proof and a more 

or less distinct sensitivity against electromagnetic phenomena. This group occasionally 

finds support of homeopaths who can base on reproducible laboratory results that fit as 

few into the view of life of science as the empirical statements of affected and possibly 

hurt people.

 

On the other side stand the representatives of the energy-supply companies and the 



runners of radio networks who argue with the needs of our modern industrial society and 

give "limits" prescribed to them by scientists. These, for their part, proceed according to 

strictly scientific methods. Their presented results are reproducible and there's no doubt 

about them.

 

The limits after all are fixed far below those that are recommended from a scientific 



viewpoint. Nevertheless both groups are separated from consensus by powers of ten. 

When we want to know how deep the ditch is we want to bridge, we should take a look at 

the determined limits (Fig. 1.1).

 

The limits stem from the 1RPA (International Radiation Protection Association) an organ



 

of the World Health Organization that in turn has appointed the INIRC (International Non

 

Ionizing Radiation Committee). These now state to have used all available scientific



 

research results as basis for the given guidelines.

 

Moreover a safety range was worked into them. So the limits were fixed at substantially



 

lower levels to guarantee that no health damage arises. In this way first the limits were

 

determined for the people who for reasons of profession are exposed to electromagnetic



 

fields.


 

For the population in general the limits for the so called non-professional exposition were

 

reduced further to one half till one fifth for reasons of caution and care. In Fig. 1.1 these



 

limits are registered. Thereby is distinguished between magnetic fields and electric fields

 

that appear stationary or at extremely low frequencies (ELF describes frequencies between



 

1 Hz and 100 Hz). Moreover limits for low-frequency (1-10 kHz) and high-frequency (1-

 

10 MHz) alternating electromagnetic fields are given.



 

The graph should serve as a rough orientation and show us the proportion of scale. As

 

further information some thresholds of measured reactions of biological systems are



 

registered (after Konig*

1

*). Because a logarithmic scale was chosen to fit all the values on



 

one graph it becomes clear that between the first reactions and the recommended limits

 

there lie up to five powers often. The ditch seems to be insurmountable.



 


4

 

Wireless telephones



 

 

Fig. 1.2:      Set of problems of environmental compatibility by 



means of the example of the handheld wireless 

telephones (handy). 



:     L.v.Klitzing: Neurophysiologische Einflusse durch elektromagnetische Felder 

wahrend und nach der Exposition, Med. Universitat zu Lubeck

 



Introduction 

5

 



1.2 Wireless telephones 

Measuring technical surveys with regard to the influence of brain currents by digital radio 

signals by the university hospital in Lubeck have startled handy manufacturers and users 

equally 


. Although in this case measurement errors could be detected, the ,,bugaboo on 

the wall" remains that we are sitting unsuspecting in a restaurant and a neighbour draws 

his handy out of his pocket to make a digital telephone call. Thereby synchronizing the 

brain currents within a radius of 100 meters on the broadcasting signal and occupying our 

brain useless with technical signals. The derivation will show that from the start this can't 

happen to all visitors, because as a prerequisite conditions of resonance must be fulfilled. 

But would there be an affected, he or she for sure would have considerable problems, 

because informations that are not picked up over the sense organs can neither be classified 

timely nor as regards content.

 

An affected whose brain has picked up technical signals not even is able to register by 



itself that it was fed with incorrect informations. It would be reasonable when the visitors 

of the restaurant would defend themselves and put the radio operator on the doorstep. The 

number of restaurants where apart from cats and dogs also handy's have to stay outside is 

increasing. How should we keep out of the way of electromagnetic fields? Should we walk 

around permanently with a steel helmet or even better in a knight's armour and even go to 

bed with them? It would be worse than in the dark middle ages.

 

Summarizing: it should be guaranteed that the operation of electro technical apparatus 



causes neither health damage nor unintentional influence or irritation. A systematic and 

scientific procedure should investigate in the laboratory all relevant physical phenomena 

individually for their interaction. Electro physics bases on two phenomena in connexion 

with electro-smog: on the one hand the radiation and on the other hand the thermal effect, 

but at a close look both factors prove to be of only little importance! 

In radiation measurements the intensity of the electromagnetic wave at a certain place is 

determined. In laboratory experiments the field strength is increased so long till biological 

reactions are observed. Thermal limits are determined in a similar way. As said, the values 

lie about powers of ten above those that possibly bother you when you hold a handy to 

your ear. It is true that the microwave radiation penetrates into your head but we also 

know that it marches out again on the other side and this visit in your head happens with 

the speed of light.

 

Exactly like this are guest in your body constantly your local radio station, your local 



television station the satellites with hundreds of programs and anyway the whole radio 

technical world even when you did not invite them.

 

For an electromagnetic wave to become receivable, the field strength must lie clearly 



above the common noise signal and this can only be achieved by a permanent overlap, by 

standing waves, like in a cavity tuned to a specific frequency or an antenna. As long as 

people don't let themselves grow antennas on their heads they hardly have to fear direct 

biological effects of electromagnetic waves.

 

That leaves as the second phenomenon the thermal effect. With a handy held to your 



cheek there comes into being a local fever in your head. But that is not at all unusual or 

unnatural for the human body. Something like that happens to a far greater degree when 

you take a hot foot bath or let yourself be irradiated at one side from the sun at a tourist 

grill.


 


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