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Some Interesting Facts About Cellphones

Did You Know?

• That a large amount of the radiation emitted by a typical cell phone, (enough to cause heating), will be absorbed by the user’s head?

• That multiple independent tests have measured up to four times the radiation coming out of the earpiece of a cellular phone, than out of the antenna?

• That a similar amount of radiation comes out from the keypad and the mouthpiece as well?

• That recent studies are showing serious bioeffects at exposures far below the current exposure standard?

• That many phones cannot even meet these arguably inadequate standards?

• That manufacturers could make the phones so less radiation would escape into the user’s head, but most are unwilling to do so, apparently because to do so would decrease their profit, and acknowledge the potential risk?

• That different brands and models of phones have widely different levels of emissions?

• That Lloyd’s of London recently refused to underwrite cellular manufacturers against possible future claims of microwave health damage?

Leakage, Standards, and Excessive Exposure

To a first approximation, four times the radiation is going into the side of your head than is actually being used to transmit a signal to the cellular tower. Four times. This level of leakage is disturbing. In one test, 3,000 µW/cm² has been measured coming out of the ear-piece of a Motorola Micro TAC phone.

In another test, three times that much was measured, and the data for the following graph was collected:

Unshielded maximum radiation level at the given lattitude 
(in mW/cm2) vs. distance along the vertical axis of 
the phone (cm) [NOTE: the emissions from the body of the 
phone were highest near the midline, and in the antenna 
region they were highest, of course, over the antenna]:


10|
  |                     x
9 |
  |
8 |                    x
  |                        x
7 |
  |                         x
6 |                  x
  |
5 |                          x
  |                                      x    x
4 |                 x               x
  |                              x
3 |                                              x
  |       x    x
2 |   x           x
  | x
1 |x
  |__________________________________________________
0       -10     -5      0       5       10      15
   antenna          earpiece          mouthpiece

      Graph provided courtesy of Emil DeToffol

Why all the leakage? It has been postulated that fundamentally, this is about keeping production costs low, that the source of the leakage is poorly matched transmitters, feeds and antennas. It is also related to the techniques used to measure the fields, and the protocols involved. Secondarily, it is about lack of shielding in the phone case.

Because the FCC is primarily concerned with making sure Cellular Phones do not interfere with other devices, they are willing to ignore what is happening in the immediate vicinity of the phone, the so-called near-field, where your head is. In a letter to FCC Chairman, Mr. William E. Kennard, Dr. David Nghiem, Ph.D, and CEO of USA Wireless, describes how none of the phones they tested met the Emissions Mask Requirements of the FCC specification.

Your Cellphone is licensed to operate at a certain frequency; however it also emits radiation at other frequencies as well. The FCC probably due mostly to it's focus on interference, sets a gain measured in decibels, for the harmonics. The third harmonic is supposed to be 1/10,000 of the fundamental frequency, but in testing, USA Wireless discovered none of the phones they tested met this Emissions Mask Requirement.

Because of all this leakage, and the proximity of the antenna, a disproportionate amount of radiation is absorbed directly into the user’s head.

Testing has shown a wide range in radiation exposure to the user of various brands and models of cellular phones. Cellular manufacturers aren’t very happy about this, and the manufacturer of the lowest emitting phone in one test was reportedly barred from using that fact to promote their product.

An underwriter for Lloyd’s of London recently made international news when he refused to underwrite cellular manufacturers against future claims due to cellular health effects. Lloyd’s took a beating on asbestos, and it looks like they are going to play it safe on this one. Lloyd’s stays in business by playing the odds, and by doing it well. That they are taking this seriously, is an indicator that we should be taking it seriously as well.

Sources:

• BBC News - Mobile phone cancer study "flawed."
  
• Kuster - Prof. Kuster, project overview.
  
• Studies - Recent compilation of studies showing potentially serious bioeffects.
  
• Personal communications with Roy Beavers, Bill P. Curry, Emil DeToffol, Libby Kelly, Chris Reuss, et. al.
• USA Wireless - Can the Industry provide much safer cellphones?
  

Coming soon: additional information and discussion on the techniques used for the various tests, and measurement protocols.

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