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Very strong RF being thrown off by CFC - health risk?

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JackP-NYC

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The other day I was IDing some wires using an inductive amp-probe and tone generator. In one area I was picking up a very strong, very loud whine (as loud and clear as if I put the probe point was directly on the tone generator clips). It turned out it was coming from a CFC floor lamp 6' away that was turned off.

The lamp is a Verilux knock off. We also have a real Verilux lamp which throws off a different sound and is only detectable from 2' away when the lamp is off. Both lamps go down to almost zero noise when they are actually turned on.

The bulb: https://www.iqlighting.com/verilux-cfml27vlx-natural-spectrum-27w-replacement.asp

Obviously there is a transformer in the lamp, which by definition is a perfect inductive transmitter, but as someone who is worried about the health risks of constant exposure to AC fields (I don't even like my electric alarm clock to close to my head when I sleep) it is a bit troubling to have the head of this strong transmitter so close to my head, and the base with the transformer so close to my body, day after day (it is a reading lamp right next to my reading chair).

Am I being paranoid, or does anyone think the RF from this is a potential health risk given that I can clearly pick it up 6' away, let alone sitting directly next to it?

Thanks
 

crutschow

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There's no real evidence that low-frequency EMI from power lines has any effect on your health, so I don't think there's anything to worry about.
But that's just my non-paranoid opinion. ;)
 

MikeMl

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As a ham, and if I was your neighbor, I would ask you to take it outside and shoot it!
 

unclejed613

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it's RF which is non-ionizing radiation, which isn't harmful unless the field strength is enough to cause heating of tissues. you are exposed to much higher levels of RF using your cell phone. the field intensity decreases as the inverse square of the distance, so if your cell phone is 1mm from your skull, and you move it to 2mm, the field strength is 1/4 of what it was at first, at 3mm it's 1/9, at 4mm it's 1/16, etc... the noise from the lamp follows the same inverse square law. for your lamp, i doubt the field strength is more than a few microvolts per meter, and since you picked it up with a magnetic probe, it's definitely at a much lower frequency than a cell phone signal.

i've had CFL lamps that emitted enough noise to add 20db to the noise floor on my ham rig. that was pretty bad, but probably not emitting enough RF to be dangerous. since the lamp was off in your case, it probably was far less than a watt (1 watt in standby mode is the maximum idle power for "Energy Star" standards if i remember correctly)
 
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MikeMl

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Is the wavelength of a cell phone 1mm?
 

unclejed613

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Is the wavelength of a cell phone 1mm?
no, it's about 30cm. i was using a 1mm distance as a field strength reference for the succeeding measurements.
 

MikeMl

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no, it's about 30cm. i was using a 1mm distance as a field strength reference for the succeeding measurements.
You seem to be implying that if I were to measure field strength at 1mm from a 40m antenna, and moved the probe one mm further from the antenna, then the field strength would be halved. AFAIK, this only works in the "far field region". The "far field" begins several tens of wavelengths from the antenna...
 

unclejed613

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You seem to be implying that if I were to measure field strength at 1mm from a 40m antenna, and moved the probe one mm further from the antenna, then the field strength would be halved. AFAIK, this only works in the "far field region". The "far field" begins several tens of wavelengths from the antenna...
i was talking about a cell phone. near field measurements actually follow an inverse cube rule, but i was trying to keep the explanation simple.
 
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