Here is a news item…
JAIPUR: In a judgment that could have nationwide impact, the Rajasthan high court on Tuesday ordered the relocation of mobile towers from educational institutions, hospitals and playgrounds in the state within two months, citing harmful electromagnetic radiation.
This news reflects a view held by a wide section of society – I have seen a news show on Indian TV in August, in which a popular actress of yesteryear strongly put forth the theory that cellphone towers are causing harm through electromagnetic radiation.
I have a lot of problems with the way this is being handled. As a Communications Engineer with 25 years of experience, certain aspects of all these arguments bother me. I have some advice to activists who voice public opinion against such engineering decisions.
Watch Out For Vested Interests
I have not heard / read strong articles rebutting this popular belief from an Engineering Fraternity – except one smart man who cleverly came on the same news show and talked about his affordable price gadget that can make EM radiation measurement!
I have also seen photographs of the latest design in base stations that manufacturers have been talking of, in recent times. A sleek “Rubik Cube” sized model with low-power consumption and suitable for in-building & small-cell deployment.
I am not insinuating that any of these people are directly / indirectly causing the above-mentioned negative opinion to further their own causes. I am merely pointing out that when public opinion turns activist, against a professional view, they have to be careful because business interests exist on either side of the opinion divide and it may try to manipulate.
Watch Out For Imprecision
From articles I have seen & talks I have heard on the subject of EM radiation hazards, I see a lot of imprecision.
For example – a recent regulatory notice for EM radiation safety had informed all mobile operators that the “SAFETY LIMIT” has been lowered by one-tenth.
Most articles of public opinion have reported it as if the mobile operators have been asked to reduce power of their transmission by one-tenth of current levels!
There is a difference between Safety Limit and Current Level!
A COAI spokesperson in the news show clarified – current levels of radiation from 90% of the installed towers across the country were already below the new safety limit and only 10% towers were known to be operating above the new limit & below the old limit.
But the activists were continuing to mix up safety-limit with current levels!
Understand The Impact Of Your Suggestions
As the networks stand today, there are a lot of coverage gaps both indoors and outdoors. Moving antennae away will only increase this problem. Further, because of the lower signal strength (and the need to maintain signal power higher than noise power) the phone will compensate by increasing its power of transmission. The phone with a 2W limit is a more harmful source than the antenna on top of a tower!
When coverage problems happen, you are affecting the ability of some people to make and receive calls. This could also have an economic impact on their lives – although it is a lesser evil than, say, getting cancer.
Understand The Magnitude
Typical GSM HF radiation comes with a median power density of 200 micro watts per square metre at 250m from antenna (NOT from the foot of the tower). This is based on a research paper about the situation in Switzerland and not that for India, though.
Assuming the body surface area to be 2 square metres, we are talking about 400 micro watts of power incident on the body at the abovementioned distance (remember the power would reduce by the square of the distance).
Compare that with UV radiation from the sun at ground level – order of 10s of Watts.
Do Not Sensationalise
In the news program, while they were continuing to mix up safety-limits with that of current levels, they were continuing to state that the Government has ordered that the signal strength be reduced by one-tenth and trying to sensationalize the fact that the signal strength was 10 times earlier.
True – they are right. But the unit – decibel – in which this is measured is a logarithmic number and as a consequence, this value corresponds to a value of “1” on that scale! I felt that there was a deliberate attempt to use the less common unit and avoid the use of the logarithmic unit because the order of magnitude. This also made me uncomfortable.
Understand The Decision Maker
Having worked in a GSM operation in the past, the power setting for transmission is an Engineering decision. These are not things that the business men nor the customer care representatives understand or have a say. So, I doubt if these values would have ever been set to a high level that is more than necessary because of the fact that the same Engineering Personnel work with these equipment (much more closer to the tower) and would not want to be affected themselves.
It is indeed a serious thing if the EM radiation causes all the health ailments that they claim happen.
This is yet to be proven – can someone commission a research and establish with statistical correlation at-least that there are serious health ailments possible at this level of radiation please?
Until a thorough academic research is done, I am not able to believe that we are living in a Microwave oven as is being made out.