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A Radio Frequency Exposure Test Finds an iPhone 11 Pro Exceeds the FCC's Limit (ieee.org) 76

An anonymous reader quotes a report from IEEE Spectrum: A test by Penumbra Brands to measure how much radiofrequency energy an iPhone 11 Pro gives off found that the phone emits more than twice the amount allowable by the U.S. Federal Communications Commission. The FCC measures exposure to RF energy as the amount of wireless power a person absorbs for each kilogram of their body. The agency calls this the specific absorption rate, or SAR. For a cellphone, the FCC's threshold of safe exposure is 1.6 watts per kilogram. Penumbra's test found that an iPhone 11 Pro emitted 3.8 W/kg.

Ryan McCaughey, Penumbra's chief technology officer, said the test was a follow up to an investigation conducted by the Chicago Tribune last year. The Tribune tested several generations of Apple, Samsung, and Motorola phones, and found that many exceeded the FCC's limit. Penumbra used RF Exposure Labs, an independent, accredited SAR testing lab for the tests (The Tribune also used the San Diego-based lab for its investigation). Penumbra was conducting the test, which also included testing an iPhone 7, to study its Alara phone cases, which the company says are designed to reduce RF exposure in a person.
It's worth noting that when the FCC conducted a follow-up investigation they did not find evidence that any of the phones exceed SAR limits. "That said, while the Tribune and Penumbra both used off-the-shelf phones, the FCC largely tested phones supplied by the manufacturers, including Apple," adds IEEE Spectrum.

Joel Moskowitz, a researcher at UC Berkeley, says that could be because there's a systematic problem with RF Exposure Lab's testing methods, or Apple rigged the software in the provided test phones to ensure they didn't put out enough power to exceed the SAR limit. Either way, both McCaughey and Moskowitz agree that the FCC's RF exposure testing is woefully out of date, as the limits reflect what the FCC deemed safe 25 years ago.
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A Radio Frequency Exposure Test Finds an iPhone 11 Pro Exceeds the FCC's Limit

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  • When I've been asked to do RF certification before it always involved writing special firmware to facilitate testing. Press a button, turn on the radio kind of thing.

    • by weilawei ( 897823 ) on Friday February 14, 2020 @06:16PM (#59729630)

      So, like VW, they faked their emissions tests?

      • by dtmos ( 447842 ) *

        So, like VW, they faked their emissions tests?

        No, because otherwise one has to figure out how much time the transmitter is on the air during the test (there's a varying duty cycle in normal operation), how much output power it is using (also varying), what frequency bands it is on, etc., all of which changes as a function of its RF environment. This also is a problem in an anechoic chamber, in that the chamber is shielded from outside signals (so that they don't corrupt the measurement, and so that the measurement is repeatable -- having the phone hit

        • dtmos, I will call you out as a bullshitting idiot.

          You don't test for RF in an anechoic chamber. You test in an RF chamber. Ir Faraday cage if that term suits you.

          I know because that it part of what I do for a living. I use calibrated antennas and pre-amps along with some nice Keysight gear to make sure the products are RF tight and within spec. There are variations in assembly and components that can cause significant differences. So, if I knew we needed to pass a test. I could send you the quietest

          • dtmos, I will call you out as a bullshitting idiot.

            You don't test for RF in an anechoic chamber.

            Blastard, "anechoic" means non-echoing and can refer to both sound and RF chambers. https://en.wikipedia.org/wiki/... [wikipedia.org]

            I know because that it part of what I did for a living. We use calibrated antennas along with some nice Techtronics gear to make sure the military products were within milspec tolerances and the anechoic chamber we used was probably the size of your house.

            A Faraday cage is used to isolate RF environments but does nothing to stop reflections. A steel box the size of your kitchen would q

            • by dtmos ( 447842 ) *

              What CaptQuark said.

              To make meaningful radiated RF measurements one needs a shielded room, so that external RF sources do not contaminate the measurements. However, the metal shielding the room also reflects signals generated inside of the room, leading to patterns of constructive and destructive interference inside the room that produce unwanted variation in the radiated fields. To solve this, anechoic material (formed into anechoic structures typically resembling elongated pyramids or cones) is placed o

          • dtmos, I will call you out as a bullshitting idiot.

            You don't test for RF in an anechoic chamber. You test in an RF chamber. Ir Faraday cage if that term suits you.

            I know because that it part of what I do for a living. I use calibrated antennas and pre-amps along with some nice Keysight gear to make sure the products are RF tight and within spec. There are variations in assembly and components that can cause significant differences. So, if I knew we needed to pass a test. I could send you the quietest units I've hit. Would that be ethical? No. Considering Apple continues to defend its tax dodges, this would seem to be in line with that thinking.

            You're an idiot.

            Anaechoic chambers are used for both audio and RF testing. They are somewhat different; but the purpose is the same.

            Remember the giant RF chamber that Apple showed-off during the "Antennagate" bullshit? That was their $100 million RF Anechoic chamber.

            https://www.fastcompany.com/16... [fastcompany.com]

            Dumbass.

      • by AmiMoJo ( 196126 )

        Quite possibly. They know the test procedure, they can limit the modem to a certain power output during it. But in the real world everyone wants 5 bars and after antennagate they might feel that cranking it up a bit is a good idea.

    • Coulda been how they were holding it.
  • by nospam007 ( 722110 ) * on Friday February 14, 2020 @05:51PM (#59729562)

    Since the average American is much fatter than the dummy used for measuring this, this is a non-issue.

    So IOW you can't give any phone to a kid.

    • Are you saying we're all going to die from heart disease (caused by being fat) and we should be lucky to live to an age where RF brain cancer is even a concern? Btw, heart disease is the #1 killer in America, but its more fun to ignore the problem and concentrate on self driving cars, where fatal auto accidents occur at 1/20th the amount as heart disease.
  • by bobstreo ( 1320787 ) on Friday February 14, 2020 @05:55PM (#59729574)

    "It's worth noting that when the FCC conducted a follow-up investigation they did not find evidence that any of the phones exceed SAR limits. "That said, while the Tribune and Penumbra both used off-the-shelf phones, the FCC largely tested phones supplied by the manufacturers, including Apple," adds IEEE Spectrum. "

    The FCC seems to be turning into the Federal Corporation Clearinghouse.

    • by YoMatt ( 21634 ) *

      The original reporting was wrong. The FCC did buy phones to test:

      Additionally, the FCC Laboratory purchased samples of the Apple iPhone XS, Samsung Galaxy S9, Motorola Moto g6 play, and BLU Vivo 5 Mini from the open market for additional testing.

      https://www.fcc.gov/document/r... [fcc.gov]

    • The key to the LYING reporting is that nicely-deemphasized word "largely".

      Which means the FCC didn't exclusively test "phones supplied by the manufacturers".

      I'm frankly ashamed of IEEE Spectrum. They used to be better than this.

  • There's not one person in the FCC with a store-bought iPhone 11 that they could put under the scope?

    • Huh? FCC doesn't do certification. 3rd party labs (accredited by the FCC) do. And when a manufacturer brings their device there, they have to be able to put it into several modes. (Like CW trasmission, and testing channels and such.)
  • by MikeDataLink ( 536925 ) on Friday February 14, 2020 @06:09PM (#59729612) Homepage Journal

    This is not news. It's a scammy case seller making a report to sell their cases.

  • "the FCC's threshold of safe exposure is 1.6 watts per kilogram. Penumbra's test found that an iPhone 11 Pro emitted 3.8 W/kg."

    If Jobs were still around, he'd say you don't weight enough.
  • by tsqr ( 808554 ) on Friday February 14, 2020 @06:13PM (#59729624)

    Penumbra's test found that an iPhone 11 Pro emitted 3.8 W/kg.

    So, if you weigh 100 kg your iPhone 11 Pro emits 380 Watts, but if you weigh 75 kg it "only" emits 285 Watts? Or is it Watts per kilogram of the test dummy's head? Please, someone tell me what I'm missing.

    The FCC's explanation [fcc.gov] isn't very helpful: ALL cell phones must meet the FCC’s RF exposure standard, which is set at a level well below that at which laboratory testing indicates, and medical and biological experts generally agree, adverse health effects could occur. For users who are concerned with the adequacy of this standard or who otherwise wish to further reduce their exposure, the most effective means to reduce exposure are to hold the cell phone away from the head or body and to use a speakerphone or hands-free accessory. These measures will generally have much more impact on RF energy absorption than the small difference in SAR between individual cell phones, which, in any event, is an unreliable comparison of RF exposure to consumers, given the variables of individual use. (emphasis added)

    • by Strill ( 6019874 )

      It's a measure of the amount of power ABSORBED per kg of flesh, not of power EMITTED. It's meant to measure how much power is being absorbed by your brain.

      https://www.oit.uci.edu/teleph... [uci.edu]
      https://www.fcc.gov/general/ra... [fcc.gov]
      https://www.fcc.gov/general/sp... [fcc.gov]

      • by BKX ( 5066 )

        So what? If you absorb 20W, then the phone better have consumed at least 20W or your test is full of shit. Overunity is nonsense. So if we are talking brain absorption then we are talking around, say, 2kg, so around 8W, but you have to at least double that to 16W because your head is only on one side of the phone, and then multiply it by some factor to account for less than unity efficiency and the fact the phone is doing stuff other than radiate, and you get that they're claiming the iPhone 11 draws someth

        • by guruevi ( 827432 )

          More than likely it's measuring the heating that occurs in a phantom (fake tissue) and extrapolating that to W/kg to calculate the SAR limit. The cellphone cannot heat up 1kg of your tissue, that'd be ~20% of your head. Instead it irradiates a very small area (wherever the phone is touching and a few mm under the skin), they measure the heat differential and then convert the delta in temperature/g to W/kg.

          Off course these things at that scale are hard to test and verify and you need some standardized testin

          • by Shaitan ( 22585 )

            Yup, and there is certainly far more at play than the simple possibility of cooking the tissue at play when talking about the brain. Heat causes expansion which can impact conductivity. The non-ionizing radiation has been shown to cause oxidation. Glucose activity has been shown. And of course brain communication via EM field effects has been demonstrated, who knows how it is being impacted. There is a lot more than just SAR to consider when determining whether or not a cell phone is impacting your brain, e

    • Safety depends on you much radiation you absorb.
      Antennas don't radiate equally in all directions. A phone which radiates more out the the back or sides is safer than one that radiates. Specific Absorbtion Rate (SAR) measures that.

      Also, different frequencies are different in how they are either absorbed by the body or pass right through. X milliwatts at 5Ghz for Wi-Fi is different from X mw at 850 Mhz for LTE. Which is different from 39Ghz for 5G.

    • Re:Wait, what? (Score:4, Informative)

      by dtmos ( 447842 ) * on Friday February 14, 2020 @06:49PM (#59729716)

      Please, someone tell me what I'm missing.

      The FCC requires [wikipedia.org]that phones sold have a SAR level at or below 1.6 watts per kilogram (W/kg) taken over the volume containing a mass of 1 gram of tissue that is absorbing the most signal.

      That is, 1.6 milliwatts per gram for the volume containing a mass of 1 gram of tissue that is absorbing the most signal. It doesn't say anything about total body absorption, average absorption, or anything else.

  • by burtosis ( 1124179 ) on Friday February 14, 2020 @06:41PM (#59729702)
    Meh, that’s about 3dBm which is not an unusual amount of variation in cheap radio chipsets. It’s probably because no one really cares and Apple, like any smartphone manufacturer, doesn’t want angry users with dropped calls and it’s not worth the money for the precision so they errd on the side of performance. Simply holding the phone differently or using it next to a conductive surface can easily be a 10x difference in power absorbed by the user.

    A sports car you say, why right this way! The average horsepower is two hundred! Sure, some may be 400 and some 100, but that’s engines for you!

    Hmmm, maybe a car analogy was a bad idea.
    • by AHuxley ( 892839 )
      Can the FCC not allow for "'holding the phone differently or using it next to a conductive surface" during its diligent testing?
      ie resulting US approval is within set US limits?
      • Can the FCC not allow for "'holding the phone differently or using it next to a conductive surface" during its diligent testing? ie resulting US approval is within set US limits?

        It’s like an above poster said. IIRC the test is with a specific setup with a specific test subject rig in an RF testing facility. The amount of power absorbed that you need to stay under is so low, it’s not going to make a difference if it’s off an order of magnitude when it comes to individual phones. In a batch of product, it’s not unusual at all to see +/- 3dBm variation. Radio has pretty extreme differences depending on the environment, I’ve designed antennas and ampl

        • Tl;dr They set the standard low to make sure 12 hr days with it pressed against your brain, even in unlikely cases, isn’t going to be a problem.

          The summary mentions that the standard is 25 years old. They should probably update the standard, not because people have changed or RF tissue heating has changed, but because the way people use phones has changed.

          25 years ago it was common for people who needed to communicate a lot to have a cellphone stuck to their head for 12 hours a day. Today, a great deal of "phone" communication is in one of many text forms: SMS/RCS, chat apps, email, etc. I personally, use voice calling a tiny fraction of what

          • by AHuxley ( 892839 )
            Re "because of changes in the way people use phones."... For the person who is not "a great deal of "phone" communication is in one of many text forms: SMS/RCS, chat apps, email, etc." and still
            has to have a "have a cellphone stuck to their head for 12 hours a day"
            Not everyone will use "speakerphone feature"... Bluetooth.. has "business meetings"... might not have that "a tiny fraction" of an expected usage change.
            People can't be expected to be using a speakerphone, be "running or biking"...
            The tests h
            • I'm sorry, your posts are simply unreadable. Learn to use sentences and paragraphs and maybe I'll engage with you. As-is, your posts are just too much work to try to extract sense from, so I don't.
          • Cellular talk time was about 50 cents per minute back then. Not many people kept talking for 12 hours a day at that rate.

            Most plans are "unlimited talk time" today. A lot of people keep talking all day long.
  • Good thing you're not using those earbuds, cause then your head is mush.

    Remember: radiation is the square of the distance. If you find your head is feeling fuzzy, move twice as far away and you cut the radiation to one-quarter. Same goes for those wireless headphones, guys.

    • Remember: radiation is the square of the distance.

      The inverse-square law only applies to distances over a few times the wavelength. At 2 GHz, the wavelength is 15 cm (6 in for the nonmetric).

      Closer by, you're in the near field. The presence of a wavelenght-sized object (head) in the near field will greatly affect how the antenna is radiating (the object becomes part of the antenna) and also how much power the driving circuit will actually send to the antenna. Depending on the exact angle, increasing the distance from 1 cm to 2 cm could just as well increas

      • by MrKaos ( 858439 )

        I use a wired headset or speaker phone to keep the thing 2-4 wavelengths away from my head to keep microwave energy away from my head. I think a lot of people tend to look at the power output maximum of 3 watts as insignificant amount of power, but what they don't look at is the amount of microwave, as opposed to radio, energy it takes to damage the brain.

        The damage from this kind of brain injury is subtle including aggression, paranoia, mood swings and a bunch of other stuff depending on where you habit

      • For that to happen, you'd have to hold the earbud wires at a specific angle, which rarely occurs in nature.

        Possible is not Probable.

  • "...FCC's RF exposure testing is woefully out of date, as the limits reflect what the FCC deemed safe 25 years ago"
    What, does it need updating to reflect the heightened sensitivities of today's cell phone users?
    Does an iPhone put out enough RF to melt snowflakes?

  • Even back in the old "motorola" flip phones, I've always use a Bluetooth headset. Plantronics made one called an M-1500 back in the day that was a two piece. One part plugged into the headphone jack and the other part you popped on your ear. I've always used BT for the phone part. Not because of "radiation" but because I prefer to NOT have my hand on my phone or my neck tilted to hold it against my head. In the car, it's hands free...otherwise, I use bluetooth.
    • Good thing Bluetooth doesn’t involve radiation!

      • You windowless basement.

        Or do you think the sun doesn't involve radiation?
        *Ionizing* radiation too.

        You know sunburn is literally radiation damage, right?
        You know the warmth you feel from the sun is the exact same effect as what that microwave OMGradiation does to you, only a thousand times stronger at the very least, right?

        Jeez, this epidemic of cluelessness has to stop.

      • Good thing Bluetooth doesn’t involve radiation!

        How much power is the Call with Wifi and Bluetooth running too ?

  • The limit is just a guess. Oh, and you're not supposed to use phones next to your body. Talking on it next to your ear? That's not how they're tested - that's way too close to your brain for it to be transmitting.

  • It's all good. The company that did the study (Penumbra Brands https://penumbrabrands.com/ [penumbrabrands.com] has Brink (Makers of the Alara radiation protecting smart phone cases https://brinkcase.com/ [brinkcase.com] under it's umbrella.

    In other news...

  • Do you know the SAR value of THE SUN??
    Remember: it *literally* gives you radiation burns.

    Meanwhile, microwave EM radiation is three orders of magnitude removed from being able to ionize anything.

    All it does, is heat up things veeeery slightly.
    You know ... like a very dim SUN!
    The only difference is that it can reach deeper tissues. I think I have seen "warming deep tissue massages" being advertised.

    By the way, to emulate a microwave oven, you need 500 UMTS phones in an active call, 1 meter away, rotating aro

    • Hmmmzz... SAR value of Sun, that would be a good comparison, unless I'm messing it up it's 100W/kg if you are a perfect black body or less if your skin tone happens to be in the normal human range.
  • by Maury Markowitz ( 452832 ) on Saturday February 15, 2020 @11:16AM (#59731080) Homepage

    "Penumbra used RF Exposure "

    Ok...

    "to study its Alara phone cases, which the company says are designed to reduce RF exposure in a person"

    I see. So a company that sells a BS product that they claim reduces RF exposure published a report stating you get too much RF. Sure, sounds totally legit.

    "FCC conducted a follow-up investigation they did not find evidence that any of the phones exceed SAR limits"

    Ok, and actual tests by the FCC did not confirm these results. Hmm.

    "could be because there's a systematic problem with RF Exposure Lab's testing methods"

    So, wait, you're doubting the methodology of the lab *you selected*?

    (from their product page)
    "Results from tests in FCC-certified labs"

    You mean, the very lab that you're complaining about?

    "'RF exposure testing is woefully out of date, as the limits reflect what the FCC deemed safe 25 years ago"

    And has that changed? They said drowning would kill you thousands of years ago, is that "woefully out of date" as well?

    What a total bunch of BS.

  • Apple marketer: "We got glowing reviews! People are all abuzz about them."

  • How do they perform if within limits?

    Perhaps cell phones would suck if they could only max out transmit power at half that tested.
    Which means that carriers might need at least double the cell towers they have now.

    Hey! Whata ya want? Good service with health issues or healthy calls that seldom get thru?
  • Unless Apple deliberately or accidentally changed something After that iPhone Passed FCC Certification, there should be nothing to worry about.

    I'm much more interested in looking-into both Penumbra's testing methodology, as well as their motivations.

    Apple wouldn't have even submitted their Production Units to the FCC if they weren't already certain through their own testing, as well as likely an independent lab's testing, that they would Pass FCC Cert.

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