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Safety Aspects of Radiofrequency Radiation

 ADDENDUM Re.: Communication Transmitter Towers (8. February, 1996 )

Having received several inquiries asking about alternatives to exposure levels currently in use I want to provide the following: The calculations are based on the electrophonic effect, which I have recommended as an adequate comparison. Those calculations lead to an ambient level of about 100 pW/cm = 0.1 nW/cm as the equivalent value at which ambient noise is perceived as "quiet" (8 db). Subliminal noise levels are here not considered.

If we accept this level as maximum for permanent exposure most populated areas in Canada are heavily overexposed already! Unless convincing data are provided one can argue that the lowest value that can be derived from existing data should prevail. Safety Code 6 allows for much higher levels which could be rejected for being inadequate and based on insufficient procedures.

The above given level still allows for the operation of systems from a technical point of view. Considering that 0.6 W = 600mW are sufficient to reach this towers with a cellular phone the opposite direction should be able to communicate with the same power level. This is technically achievable !

Safe distance calculation based on this level of 100 pW/cm

here are some examples:

According to my local office of Industry Canada the normal output is on average 70W but up to 10 channels are allowed so the maximum output at such towers can be 700W and the safe distance would then be 7.5 km (4.6 miles).If 400 m (1330 ft) is the distance from a 300 ft (100m ) tower the maximum power at this site should not exceed 2 W ! With 10 channels on one site operated with 3W each, the same as car phones and bag phones, the total output would be 30 W. The safe distance for such a site would be 1600m (~ 1 mile ). In many cases these distances are not maintained and the allowable power exceeds the above given values excessively. Using this value would translate to a safe distance from a tower with 100 W radiation power of about 2.8 km (1.75 miles).

The calcuations assume a permanent radio output, as it is the case with most cellular communication towers .

They do not take in consideration other sources of radiation like TV, or Radio transmitters. If there are more transmitters in the vicinity the radiation has to be added up, consequently reducing the power at the new site, or moving it to a safe distance that the combined levels are below this value.

It is to be expected that this level will be dismissed as unrealisticly low, but even if higher levels would be proven guaranteed safe one should demand that only the lowest possible level is permitted that still allows the operation of the system (energy conservation). There may be some technical adjustments necessary, but that should be done! The operation of the system is generally not jeopardized with lower power.

This can not be set aside only for the reason that Safety Code 6 allows higher levels. One could even take the position that there is no specific reference in the code at all, so zero tolerance is valid until the code refers to accumulative permanent exposure. The code is still only refering to occupational exposure. Considering that the exposure of the public is involuntary and permanent, asking for power limits to such transmitters seems quite reasonable, and it is technically possible and justifiable.

However, the currently permitted levels of radiation are more than hundred thousand times higher ! With the powerful interest of the industries in this field unfortunately no change is to be expected.

Update September 1997 :

The new review of Safety Code 6 in its preliminary form has again no accumulative limits, it will state and allow permanent public exposure levels (accumulative over 24 hours) nearly equivalent to those for worktime occupational exposure ( 8 hours). Professionals in this field are well payed and covered by disability insurance - the unaware public is not "protected". The radio/micro wave pollution continues to increase steadily.

Update February 1998:

The World Health Organisation WHO has called for a symposium on the health hazards of wireless communications citing such possible dangers as tumors and cancers caused by the use of modern telecommunication devices. Hopefully this will lead to new research and better standards and not only to a whitewash on behalf of the industry.

posted 01/11/1997

copyright 1997   by Wolfgang W. Scherer

for comments or questions e-mail the author Wolfgang W. Scherer

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