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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.
Pocket or clip we are talking about non-ionizing em radiation.
See my blog http://ilovecookes.blogspot.com/ for light hearted technical information.
Once upon a time, almost no one had cell phones. Now, almost everyone does have them, and many use them constantly. To my knowledge, there has not been a statistically significant increase in the incidence of brain cancer between these two eras. I conclude from this that cell phone use cannot be much of a risk as a cause of brain cancer.
"That was an example of taking a good point and stretching it..."
Wouldn't that be a line?
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.
Block both sides and it prevents annoying calls, and provides privacy at the airport.
Though for the latter I always just wanted to get the little lead letters they used to use for marking x-rays and sew messages like "private area" or "get a real job" into my pants.
"I opened my eyes, and everything went dark again"
What makes it particularly ironic is that the same people who fear that their cell phones are harming them are probably deliberately exposing themselves to a source of ionizing radiation every time they walk outside in the daytime, i.e. the sun - a giant nuclear reactor that kills thousands of people each year from skin cancer.
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.