Earth's Magnetic Field vs Cell Phone EMF

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The Earth's magnetic field ranges from 0.3 to 0.6G, while cell phone emissions are around 2mG, raising questions about the significance of low-grade EMF exposure from devices. A tri-field meter revealed that household appliances with electric motors emit significantly higher EMF levels than cell phones, with the highest readings coming from devices like corded hair clippers. However, concerns about cell phone radiation are complicated by the fact that typical meters do not measure radio frequency fields, which are crucial for understanding cell phone emissions. Additionally, body interaction with EMF is frequency-dependent, with lower frequencies passing through the body more easily. Ultimately, the energy absorbed from devices like Bluetooth headsets is still much less than natural sunlight exposure.
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If the Earth's magnetic field as measured on the surface of the Earth is somewhere between .3 and .6G and cell phone doses are around 2mG, is it then absurd to be at all concerned with even heavy exposures to the kind of low grade doses that cell phones and other electrical devices produce?

I recently purchased a "tri-field meter" for fun and I found that everything with an electric motor in the home produces far more EMF than a cell phone, even right next to it during a call. The highest reading I got was from a corded electric hair clipper. That pegged the scale, which goes up to 100 mG. While I'm not too concerned about the cell phone, I wonder about other devices. An MRI is something like 10,000G, so I don't think it's out of the realm of possibility that it could have some effect, although even at that strength it's doubtful that it could ever alter DNA like a standard ionizing radiation X-ray can.

Any thoughts?
 
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First, your meter does not register radio frequency fields and is therefore of no use in characterizing the radiation from cell phones. Depending on the type of service, a phone radiates in the UHF (GSM, 900 MHz) or microwave (CDMA, PCS at 1900 MHz). Second, body interactions are frequency dependent. Very low frequencies mostly pass right through. Bluetooth headsets, on the other hand, radiate in the unregulated ISM band that is also shared by microwave ovens, where the body absorbs virtually 100% of the energy.

BTW, emf is different than magnetic field.
 
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marcusl said:
Bluetooth headsets, on the other hand, radiate in the unregulated ISM band that is also shared by microwave ovens, where the body absorbs virtually 100% of the energy.

The energy of the photons your body absorbs is still much less than that of the sun. You'll do more harm standing outside than using a Bluetooth headset.
 
It may be shown from the equations of electromagnetism, by James Clerk Maxwell in the 1860’s, that the speed of light in the vacuum of free space is related to electric permittivity (ϵ) and magnetic permeability (μ) by the equation: c=1/√( μ ϵ ) . This value is a constant for the vacuum of free space and is independent of the motion of the observer. It was this fact, in part, that led Albert Einstein to Special Relativity.
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