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Cell Phone Radiation Emission Tests Assume Use of Belt Clip
jfruh writes: Most Slashdotters rightfully roll their eyes when people panic about the "radiation" put out by cell phone. But there is a germ of truth to some of the nervous talk: when the FCC assesses how much radio-frequency radiation a phone user will absorb, they work on the assumption you'll be wearing it in a belt clip, rather than putting it in your pocket as most people do. With the size of some recent phones, I think assuming use of a backpack might be just as realistic.
The belt clip keeps it closer to my genitalia. So I think that is the conservative testing location.
Seriously, this is utter nonsense.
Is SAR testing performed in body worn configuration using the belt clip? Sure it is. It is also done and various angles.
It is also tested against the head. It is also tested with a 1-5 mm separation distance. It is also tested with direct contact, and against the head, and extremities.
SAR is tested in a lot of configurations. Belt clips are just one of them.
Also, the author of the article clearly does not understand waveforms.
Putting a phone in your pocket does NOT mean that your exposure is higher than when using a belt clip having an 8mm separation distance. In fact, it is very often the case that the slight separation yields a higher power density than direct contact. This is of course due to the wavelength of that particular frequency.
Actually, there should not be any phones transmitting at 3 watts.
The highest in the US is GSM in the 850 MHz band. That is 2 watts, or 33 dBm.
Of course, nowadays most phones are using either UMTS or LTE.
So, in the same band, or any band for that matter will have a maximum output power of 24 dBm or 251 mW. Of course, by law you can transmit up to 7 Watts in some bands, but the networks do not allow for these high power class devices, so 24 dBm is the highest you will see as a consumer.