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Cellphones Handhelds

Cell Phone Radiation Emission Tests Assume Use of Belt Clip 184

Posted by timothy from the like-everyone-uses dept.
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.
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Cell Phone Radiation Emission Tests Assume Use of Belt Clip More

Cell Phone Radiation Emission Tests Assume Use of Belt Clip

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

    • Re: Taking a good point and stretching it. (Score:2, Funny)

      by 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.

    • ..and so? (Score:4, Informative)

      by Geoffrey.landis ( 926948 ) on Tuesday July 14, 2015 @11:15AM (#50108249) Homepage

      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... [physicscentral.com]

      • Re:..and so? (Score:5, Insightful)

        by timholman ( 71886 ) on Tuesday July 14, 2015 @12:02PM (#50108715)

        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:..and so? (too many WATTS) (Score:5, Informative)

        by pablo_max ( 626328 ) on Tuesday July 14, 2015 @12:16PM (#50108841)

        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.

        • Actually, there should not be any phones transmitting at 3 watts.

          Today, that is correct.

          However, the first-generation analog cellular phones broadcast at a maximum of 3 watts. Only car-phones and bag-phones got that high, though.

        • The only way I know of today to get over about 1/4 watt today isn't with a cell phone, but a dedicated repeater(for cellular traffic). Dad's work just bought one for a truck. That can transmit at maximum power, but that's to an outside antenna.

          You can also get higher powers with other bands.

          My favorite is the woman using a portable phone handset because she didn't trust cellular radiation...

    • Comment removed based on user account deletion

      • Re:Taking a good point and stretching it. (Score:4, Funny)

        by nospam007 ( 722110 ) * on Tuesday July 14, 2015 @11:28AM (#50108401)

        "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.

      • 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. (Score:5, Funny)

      by nospam007 ( 722110 ) * on Tuesday July 14, 2015 @11:22AM (#50108349)

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

      Wouldn't that be a line?

    • 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.

    • On the other hand, for about half the population, they are purse phones.

  • Does not really matter. (Score:5, Insightful)

    by LWATCDR ( 28044 ) on Tuesday July 14, 2015 @11:08AM (#50108165) Homepage Journal

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

    • Re:Does not really matter. (Score:5, Informative)

      by Mr D from 63 ( 3395377 ) on Tuesday July 14, 2015 @11:09AM (#50108175)
      The belt clip keeps it closer to my genitalia. So I think that is the conservative testing location.

    • 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.

      • ...(C)lips have a metal spring. This spring can have a coupling affect and change the radiation pattern of the phone.

        Pockets and purses can have coins while backpacks can have lots of metal items. It really doesn't matter, though, as the damage likely, if any, has already been done.

    • So? You think radiation is only dangerous when it's ionizing? UV isn't ionizing, neither are microwaves.

      • Re: (Score:2)

        by barakn ( 641218 )

        UV isn't ionizing? My god, you've just undone a century of physics. Go collect your Nobel prize.

      • Re: (Score:3)

        by LWATCDR ( 28044 )

        " 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.

  • My thigh muscles might be slightly warmed. How terrible.

    • My thigh muscles might be slightly warmed. How terrible.

      In most places you have to pay extra for that.

  • Mechanism? (Score:4, Informative)

    by Cafe Alpha ( 891670 ) on Tuesday July 14, 2015 @11:09AM (#50108183) Journal

    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: (Score:3, Informative)

      by Cafe Alpha ( 891670 )

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

    • Re:Mechanism? (Score:4, Insightful)

      by h0oam1 ( 533917 ) on Tuesday July 14, 2015 @11:20AM (#50108317)
      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.

      • 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.

        Are you someone we would expect to be familiar with brain cancer rates both before and after the advent of the cellular telephone? And if not, why wouldn't we expect you to have gone looking for some sort of citation instead of just speculating? I mean, as far as I know you're right, but as far as I know you're wrong.

      • 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

        • 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: (Score:2)

        by trampel ( 464001 )

        Obligatory xkcd: https://xkcd.com/925/ [xkcd.com]

    • Re: (Score:2)

      by AmiMoJo ( 196126 )

      The mechanism is thought to be heating. It applies to other RF devices too, e.g. wifi which is a very low power microwave oven. The thing is, you would need a great deal of exposure for extended periods of time at high signal strength for it have a measurable effect. So, unless you sleep with it taped to your head in a low signal area...

    • Causation is reversed. Obviously brain cancer causes people to do abnormal things, like keep devices pasted to the side of their head instead of talking to people in the surrounding environment.

      • Unnecessarily encouraging interaction from these hostile creatures in my surrounding environment seems like a very abnormal thing to do.

    • 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: (Score:2)

        by bws111 ( 1216812 )

        Any evidence to support your claim that exposure to micowaves is not a bright idea?

      • Higher-frequency UV is ionizing, lower-frequency isn't. Energy from non-ionizing radiation turns into heat, not any sort of chemical change. Given the power levels, it's probably more dangerous to wear a hat.

        And what established result do we have? From what I've seen, nobody's found any ill results of the radiation from cell phones (as opposed to, say, distraction by cell phones while driving).

      • Re: (Score:2)

        by mjwx ( 966435 )

        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.

        Fuck me.

        Nebulous "energy" is at the centre of most quackery and cargo cult science.

        "Energy" is not descriptive enough to be able to say whether something is a risk or not. You need to define what the energy is, what it does and how this affects us (or whatever the subject of your experiment is). So whether radiation is ionising or not is entirely relevant, especially when drawing conclusions about long term health effects.

        Simply saying that "energy" goes "somewhere" is completely useless and only

    • When there's no known mechanism, you are likely dealing with a correlation rather than causation. Perhaps people at risk of getting brain cancer are also more likely to use a cell phone? (This would also explain the sibling post's lack of increase in brain cancer).

    • It is known that an electric field can affect cell growth. https://en.wikipedia.org/wiki/... [wikipedia.org] It is also known that radio waves can be converted to an electric field, so in theory a cellphone could affect you. Note that the EM field from your house wiring is much stronger and always transmitting, so more likely to affect you.

  • Million dollar idea... (Score:4, Funny)

    by funwithBSD ( 245349 ) on Tuesday July 14, 2015 @11:11AM (#50108207)

    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: (Score:2, Funny)

      by Nidi62 ( 1525137 )
      With the latest trend of workout clothes sewn with copper thread to supposedly help with pain or circulation of something (and let's not forget those magical magnetic wristbands that do everything from stopping arthritis pain to curing cancer), you could easily sell a pair of pants with a pocket lined with copper fibers that would "block harmful radiation". Of course, it would possibly also block reception, but whatever.

    • Re:Million dollar idea... (Score:5, Funny)

      by TheCarp ( 96830 ) <sjc.carpanet@net> on Tuesday July 14, 2015 @11:25AM (#50108381) Homepage

      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.

      • hmm... improvement:

        Fully line the left pocket, half line the right pocket...

        protection from toxic radiation or protection from toxic ex... take your pick!

    • It would probably work, in the sense that it would reflect power away from your body and towards where it's useful, improving battery life (slightly).

    • There's a company in china selling supposedly low power tablets and phones for pregnant women so their developing babies won't have any defects from the radiation.

  • Complete and Utter nonsense (Score:5, Informative)

    by pablo_max ( 626328 ) on Tuesday July 14, 2015 @11:23AM (#50108361)

    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.

  • I keep mine ... (Score:4, Funny)

    by PPH ( 736903 ) on Tuesday July 14, 2015 @11:28AM (#50108403)

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

    And by "gun" I mean gun.

  • What? (Score:2)

    by wbr1 ( 2538558 )
    You don't all use these: http://www.amazon.com/Cell-Pho... [amazon.com] ????
  • Suppose some way beyond the worst case scenarios were proven, and doctors could assert, "Give up using cell phones cold turkey or you'll suffer the same health risks as smoking cigarettes." How many people heavily dependent on using cell phones would give them up? How many would be able to pry them from the fingers of their teenagers? I am guessing not many. Going out on the street whether driving, walking, or biking is also incredibly dangerous, well except maybe for Sweden eventually. But we do it an

  • Here [forbesimg.com] is the graph that should put this entire debate to rest. Even though the number of cell phones in use has skyrocketed since 1999 the incidence of brain cancer has not. If there was any causation one would expect an increase in brain cancer. That has not occurred. No correlation therefore no causation.

    (please note that correlation can disprove causation but not prove causation)

  • Can't anyone do simple arithmetic? Why not fear being illuminated by a flashlight? Ooooo, a death ray!

    Non-ionizing radiation at a total radiated power order of watts. Why not worry about your microwave oven? Or turning on the lights when you come home in the evening. Or turning on the heat in your house? Or going outside on a sunny day? Or living in the mountains? Or living in a house with a concrete foundation? Or eating almost anything? Or getting hit by lightning? Or (fill in a huge, truly eno

  • With the size of some recent phones, I think assuming use of a backpack might be just as realistic.

    With the ever increasing ubiquity of internet addiction, I think assuming that some phones almost never leave the owners hand might also be realistic. (And yeah... I'll confess that I'm speaking for myself, to some degree.)

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