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.

Comments

Does not really matter.

[LWATCDR]

Pocket or clip we are talking about non-ionizing em radiation.

Re:Does not really matter.

[Mr D from 63]

The belt clip keeps it closer to my genitalia. So I think that is the conservative testing location.

Re:Does not really matter.

[flopsquad]

A belt clip is closer to your genitals than the inside of a front pocket?

I use the iCodpiece, you insensitive clod!

Re:Does not really matter.

[msauve]

" Who keeps their phone in a front pants pocket?"

People who've broken a phone by sitting on it while it's in their back pocket.

Re:Does not really matter.

[pablo_max]

Actually, it does matter.
You will find that often times the belt clip gives a higher power density measurement than direct contact, This is normally down to two factors.
The wavelength of the band and the fact that most clips have a metal spring. This spring can have a coupling affect and change the radiation pattern of the phone.

Re:Does not really matter.

[LWATCDR]

" UV isn't ionizing at least the far UV bands are, the lower bands are close enough in energy to cause photochemical reactions that break bonds so they are treated as ionizing radiation"
So yes it is.

With EM non-ionizing radiation in the RF bands the only concern is tissue heating. Even with the standard inverse square law at the standard transmission power of a phone the difference in the heating effect between a belt clip and a phone in your pocket would not be significant.

Re:Does not really matter.

[amRadioHed]

UV is ionizing and it isn't. Depends on the frequency. The wikipedia article says that, maybe you should read it.

Re:Does not really matter.

[currently_awake]

Using your back pants pockets causes uneven sitting levels, that causes chronic back pain. You should never use your back pants pockets for anything.

Mechanism?

[Cafe Alpha]

While there's a European study suggesting that using a cell phone against your head increases your risk of brain cancer (by a factor of 2 I think), there's no known MECHANISM for this, since radio waves are not ionizing radiation.

Re:Mechanism?

[Cafe Alpha]

Note, a multiple of a small number is still a small number. https://xkcd.com/1252/

Re:Mechanism?

[h0oam1]

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.

Re:Mechanism?

[Anonymous Coward]

No.

What we know is that "P implies Q", where P=causation and Q=correlation.

The fallacy everyone points out is "Q implies P". This is the CONVERSE of the above, and its truth is NOT implied by the above. That's what makes is a fallacy.

However, "not-Q implies not-P" is the CONTRAPOSITIVE, and its truth IS implied by the above. Therefore, lack of correlation DOES imply lack of causation. h0oam1 is therefore correct.

Re:Mechanism?

[iMadeGhostzilla]

But smartphones with stronger radiation and ultrafast processors and whatnot have been around for a relatively short time.

Here, I just randomly picked a popular phone from 2006, Morotola Razr, and Motorola Turbo Droid, from 2014:

Razr SAR rating:

Head:
0.31 W/kg
Measured in:
1900 MHz
Body:
0.35 W/kg
Measured in:
1900 MHz

Droid Turbo SAR rating:
SAR US 1.39 W/kg (head) 0.50 W/kg (body)

Just two points but I imagine more search would show the trend is that SAR is getting higher.

I assume there is a point where harm begins to show -- imagine you build a phone with SAR rating of 100W/kg and use it every day. Would the effect show in 100 years, 50 years, 10, 1, six months...? So the question is where that point is for the what seems like a very common 1.39W/kg.

And then there is the question how reliable SAR is as a measure of effect of radiation on the tissue. From the Wiki page: "SAR limits set by law don't consider that the human body is particularly sensitive to the power peaks or frequencies responsible for the microwave hearing effect.[5][6] Frey reports that the microwave hearing effect occurs with average power density exposures of 400 w/cm2, well below SAR limits (as set by government regulations)"

I don't think it's unreasonable to say that not enough time has passed for the new generation of phones to rely on it as evidence of safety.

Re:Mechanism?

[Zalbik]

I'd mod you up, but you're AC.

So here...have a doughnut: O

Re:Mechanism?

[DerekLyons]

UV isn't ionizing either. Neither are microwaves. Prolonged exposure to either is... not a really bright idea.

So please, let's leave off the cargo cult science babble about "cell phones don't emit ionizing radiation". They emit energy, and that energy goes somewere. Nor do we need a mechanism when we have an established result.

Re:Mechanism?

[Carewolf]

But smartphones with stronger radiation and ultrafast processors and whatnot have been around for a relatively short time.

Nope. The original generation of mobile phones had stronger radition. Then they set much smaller limits and made everything more efficient, so now phones emit much less energy.

Re: Taking a good point and stretching it.

[Anonymous Coward]

That was an example of taking a good point and stretching it... Even the biggest 'smart' phones are pocket phones.

I'm a nudist you insensitive clod.

Re: Taking a good point and stretching it.

[Travis Mansbridge]

Just use nature's pocket!

Million dollar idea...

[funwithBSD]

Jeans and Khaki's that have the inside of the pocket lined with EMF blocking material. Just next to the skin, or it would block the phone from working.

Make a "pocket protector" version to use with any standard pair of pants.

it will never work... perfect for kickstarter.

Re:Million dollar idea...

[TheCarp]

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.

..and so?

[Geoffrey.landis]

I'm just not sure why we should care. There are no known non-thermal effects of microwaves, and the thermal energy of a cell phone just isn't enough to pay attention to-- three watts, when it's transmitting at full power.

http://physicsbuzz.physicscent...

Re:..and so?

[timholman]

I'm just not sure why we should care. There are no known non-thermal effects of microwaves, and the thermal energy of a cell phone just isn't enough to pay attention to-- three watts, when it's transmitting at full power.

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.

Re: Taking a good point and stretching it.

[Cafe Alpha]

http://gizmodo.com/5853495/yes...

Re:Taking a good point and stretching it.

[nospam007]

"That was an example of taking a good point and stretching it..."

Wouldn't that be a line?

Complete and Utter nonsense

[pablo_max]

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.

Re:Taking a good point and stretching it.

[nospam007]

"Have you seen women's pants lately?"

Only the inside.

But seriously, 'lately'?

Have you ever checked women's skirts, robes, dresses for the last couple of hundred years for pockets?

That's why they invented handbags. If you ever checked a woman's purse, those wouldn't fit in any imaginable pocket anyway.

I keep mine ...

[PPH]

... in my fanny pack. So it can keep my "gun" warm.

And by "gun" I mean gun.

Re:Taking a good point and stretching it.

[pr0fessor]

Did you entirely miss the phablet craze, or do you just have huge pockets? 5.5 inch is fairly common but they don't fit in my pockets unless I'm wearing cargoes.

Re: Taking a good point and stretching it.

[slimshady76]

That certainly gives "bendgate" a new perspective...

Re:..and so? (too many WATTS)

[pablo_max]

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.

Re:Taking a good point and stretching it.

[ClickOnThis]

Have you seen women's pants lately? A lot of them don't even have real pockets (seriously, they're just decorative), and the ones that do are tiny. You'd have trouble fitting a relatively tiny 3" phone in there, let alone some of the 5" phablets you see nowadays.

Whoa ... take a breath, dude. How many hands did you use to type that?

Re:Taking a good point and stretching it.

[Anonymous Coward]

I am pretty sure a man invented handbags.

and used to carry them, too. The old word for a pick-pocket was a cut-purse, meaning somebody who cuts the straps on a man's purse and runs away with it. Men carried handbags. And the old word for a bag, of course, is "poke" (as in: "don't buy a pig in a poke"). When they first came up with the idea of sewing the purse right into a pair of pants, they called the result a little poke: pok-ette. Or, as we say now, pocket.

Re: Taking a good point and stretching it.

[davester666]

I am not following any link posted in response to the GP's comment.