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Comment by jws | Hacker News Reader

Testing phones from 5 millimeters away from the body may seem close, but for anyone carrying their phone in a pocket, the distance is closer to 2 millimeters. Because wireless power falls off exponentially with distance, what might be a safe amount of RF exposure at 5 millimeters could be much higher at 2 millimeters.

They mean to say that you should expect a power about 6 times higher, (5^2 / 2^2). This is rubbish.

The square of the distance model is for a pair of points. Phones in pockets at such closed distances are more closely modeled by a pair of infinite planes where the power falls off not at all. The real result will be in between, but very much closer to 1 than 6.

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FWIW when you're closer to an antenna than the wavelength, you're not just seeing normal Gauss's law drop off, you can be looking an an evanescent wave [1], which does indeed fall off exponentially (well, depends on the exact shape of the antenna).

I've designed a short-range 'antenna' that is intentionally not impedance matched to the vacuum, and radiates very poorly - but the RF intensity close to the antenna is very high because of this effect.

[1] https://en.m.wikipedia.org/wiki/Evanescent_field

Cool. Could this be used for wireless charging and/or less snoopable RFID/contactless replacement?

Well you are in the reactive near-field, so the antenna will de-tune, hence the power amplifier won't see it's ideal match, and not deliver as much power. All depends on antenna design and orientation, assuming they don't use active impedance tuning.

The base station also tells the phone to back-off. If the TX were running at full power, the battery will die quickly. Leave your phone in a metal, security cubby and your battery will die quickly; no power control and worse-case antenna loading.

Also the highly asymmetric data usage these days. Very little energy on the uplink.

FWIW I design antennas and amplifiers for a living. The only time I'd worry about RF exposure is to the cornea; that is a proven hazard. RF burns are a right of passage for PA designers, and are harmless as it's the outer skin layers.

> Leave your phone in a metal, security cubby and your battery will die quickly

Which is the best selfish reason to remember to switch on flight mode on an aeroplane. (Also when you’re trekking in areas where you know cell coverage is nonexistent.)

> RF burns are a right of passage for PA designers, and are harmless as it's the outer skin layers.

A literal example of skin effect?

Yep. Put your finger on the corner of the output coupling cap on a 50 Watt S-band PA. It will turn your skin black from the charring, but doesn't penetrate into the live tissue. Just don't leave it on too long.

Could probably gives non-permanent tattoos with this method.

> If the TX were running at full power ... Leave your phone in a metal, security cubby and your battery will die quickly

If the phone can't hear a network (not just faint signal like airplanes on certain heights), would it actually transmit?

I think the battery drain would be from active RX searching for networks instead of sleeping. You get a similar though probably lower effect, when in roaming without setting a fixed network - an idle phone without crapware will burn way more energy.

So it is doubly incorrect... They are completely misusing the word exponential to mean quadratic which is already incredibly annoying, but it is not even quadratic, it is constant.

Not squared, inverse square. That's faster than exponential.

You may need to check your math. Inverse square does not fall off faster than exponential.

1/x² has a singularity and rises faster than exponential as you approach it. We're talking about getting closer to the source, not further.

Ah, I see. In that direction, you are correct.

It should be obvious that real world antenna don’t behave this way as they are not point sources. But, mathematically you’re correct.

As you get closer and closer to the surface of the phone, phenomena progress from a visible glow, to pair production, to the thermodynamic stability of quark-gluon plasma.

No. All polynomials and rational functions fall off drastically slower than exponential.

We're talking about the rise in power as you get closer. 1/x² has a singularity, I doubt exp(x) can beat that...

Good point! -ln(x) may (would have to check), but exp(0) = 1 and 1/02 is defined as positive infinity (the Real numbers are not closed under division).

No, division just isn't a total function.

I think these may be the same thing in this case.

I'm following along in this thread here and double checking everybody's math.

So... does this mean I will die from radiation or not?

This thread is actually irrelevant to the radiation question due to the plane radiator thing mentioned above.

Exactly. Near field electromagnetic variations are not inverse square.

"Phones in pockets..."

The somewhat related study mentioned in the article was much more interesting in terms of "phones in pockets".

https://www.jstage.jst.go.jp/article/tjem/248/3/248_169/_art...

I wonder if we shall take exposure density into consideration? If RF is emitted in all directions, the closer the phone to the body, the same amount of RF will be received by a smaller area of skin?

You’re still thinking about a point source, where the actual scenario is closer to two parallel plates, in which case the non-normal components cancel out, leaving only the normal component, except at the edges.

The most basic example from electrostatics: http://hyperphysics.phy-astr.gsu.edu/hbase/electric/elesht.h...

I don't think the phone emits radiation from its entire body

That's what the cuts around the metal band of the iPhone are for, to segment the edge into different tuned antennas.

If you try to make an antenna too small compared to wavelength, it will become less efficient and more difficult to design. 900 MHz is the 33 cm band, so if you have a more standard size antenna on the order of quarter-wavelength size, you get an antenna that’s about 8cm.

Why isn't it tested at 2mm if that is the standard useage?

Why rely on a model?

20,000 phones are being sold an hour. Why not buy 200 phone's off 200 shelves and test them comprehensively at 0 mm, 1mm, 2mm, 3mm ..... The cost to volume sold is completely negligible and it is useful consumer information as 3 percent of the population is electrosensitive.

An estimated 30 million people suffer from Myalgic Encephalomyelitis (chronic fatigue) in the world and the average diagnosis takes seven years. Chronic health conditions are increasing exponentially. Healthy people aren't sensitive to environmental stimuli but unhealthy people are and the number of chronically unhealthy people grows by the day as livers strain under the stressors and weakening of modernity.

Turn your wifi off in your house at night and see if you sleep any better. Pretty simple anecdotal experiment. A house without the wifi on or excess electrical componentry on has a nicer feel. We did not evolve with this electromagnetic radiation and the cost of testing is negilible given the global population's growing exposure to it and something interesting may fall out of the research.

The risk of Apple having to make slight design modifications if research raises an issue is not a huge concern of mine. One hours phone sales should cover it and then they could further differentiate their products and raise prices.

How many electrical engineering schools are there in the world? Sounds like a great way for a university to get their staff free Iphones with a research grant.

Electrosensitivity is not a thing.

It's a disorder made up by hypochondriacs. If you said 3 percent of the population are hypochondriacs then I would believe you.

It's interesting how certain you are. What you mean to say is "we've never seen scientific evidence that Electrosensitivity is real, therefore as we currently understand it can't be".

Much like the Earth going around the sun, bacon causing cancer, BPA in plastic being bad (and now the substitutes too) etc. etc.

It's always not true until we discover it is.

Don’t forget these peoples ‘senses’ are easily disproved by blind tests. It’s much more of a hoax than you imply.

One will become electrosensitive in a dryer climate.

capacitive touch is derived by galvanic response that can be impacted by pH balance and electrochemistry.

potassium is used to reduce the impacts of gamma radiation (wrong band, but not irrelevent)

microwaves can be lethal from a distance of 1 km (death ray)

there is so much radiation in the air, to study the affects of one wave length i'd suppose you'd need multiple band pass filters to narrow the band in question and a noise generator for controlled results.

Missing "References" section, the formatting of your paper could also be improved. /s

I don't doubt that psychosoma and hypochondria play a role in many cases, but I will posit a couple of scenarios for you to ponder.

You can sense heat, can't you? If your phone is really warm in your pocket, will you notice? Higher output from the radios = more electricity flowing = more heat generation. You will likely notice this.

On another note, do you have eyes? They are sensitive to various frequencies of electromagnetic radiation (i.e, the visible spectrum). Some people are more attuned to the outer edges of this (infrared, and ultra-violet).

Seems a bit aggressive to dismiss all electrosensitivity as "not a thing", considering people are obviously very sensitive to different forms of EMR.

If you disagree, try standing in a fire, or sleeping with a spotlight on your face.

The maximum amount of power emitted from a WiFi radio in the US as regulated by the FCC is 0.071W. You're not realistically going to notice much heating from WiFi. Have you ever tried to cook something on the antenna of your WiFi? Try putting a cup of water next to your WiFi router and measure the temperature difference. You'd need massively super-human levels of sensitivity to begin to notice any warming effects. Sure, if you crank the output up to a few dozen watts you'll definitely start feeling the effects of RF. Get it a few dozen watts higher and you'll be at risk of getting RF burns after some prolonged exposure. Get it several hundred watts higher and you're cooking a dinner in the metal box.

As for possibly almost seeing things like WiFi, that's also pretty preposterous. WiFi operates at 2.4 or 5.8GHz. Your eyes start to get sensitive EM waves at about 4000000000GHz (lower end of what is commonly called visible spectrum). Even if you were at the ultra extreme low end of sensitivity, you still wouldn't really be anywhere near the frequency range required.

So for your example of standing in a fire or having a spotlight on your face, you'd need for it to be a practically room temperature fire or a millionth of a candle spotlight. The scales you're comparing to are just silly to the point of being meaningless.

Electrosensitivity is denied by intelligent healthy people who have never dealt with unexplainable fatigue relying on statistics and body system diagnosis that is inadequate for explaining chronic complex health conditions.

They're all just whinging man. Not one of them ever hoped it was all in their head and they could think their way out of it.

Hacker News is a perfect subset of people lacking the perspective to consider exploring the possibility that electrosensitivity is a thing that occurs with declining health.

Why so much negativity about researching something so ubiquitous? Let's discuss inverse power laws and quadratic functions, maybe we can build a machine learning model with our deficient statistics instead of taking two hundred phones out of two billion and testing their electromagnetic radiation at multiple distances and angles so we actually have a reliable model.

> Why so much negativity about researching something so ubiquitous?

There's nothing wrong with researching electrosensitivity to see if it's real, and to what extent. Heck, I've designed studies to test it (never carried out). The problem is not researching it, yet continuing to insist that it is the reason for people's "unexplainable" chronic pain / fatigue when there's currently zero non-anecdotal evidence for it.

I'm very much in favor of researching electrosensitivity. Whatever the cause, it's undeniable that certain illness patterns are becoming increasingly prevalent.

But I'm not really seeing research from electrosensitivity proponents, and especially not double blind studies. Instead, I'm seeing requests for fairly massive accommodations (along the lines of eliminating all Wifi and Cell phone radiation within a certain radius of a person), backed by not a whole lot of scientific evidence (unless one counts "Rudolf Steiner would have said so" as scientific evidence).

And I'm not even seeing many reports of such accommodations working to the long term benefit of the sufferers. Instead, once the Wifi is gone, they seem to develop MCS, etc. To me, that would support the prior that the suffering (which itself is undoubtedly real) is likely to have endogenous rather than environmental causes.

I agree. It’s a very small component of the overall health picture. But it is a component and should be researched.

Once the wifis gone the MCS patients spend more time sitting in front of wired digital display devices activating their central cortexes burning through their constrained glutamate supplies (which is also the most probable reason blind people don’t develop schizophrenia)which depletes their glutathione which increases their pathogenic load and inflammation while their spinal column is degenerating and inflaming from the sitting and those two things have a larger negative effect on them than the positive effect of the reduction in wifi exposure.

The disappointment at their failed remedy further aggravates their condition and nobody is interested in their next bright idea for alleviating their condition. So they live their life out labelled as a whinger and their negative emotions contribute further to their health decline.

They won't recover while exposed to er but because removing er won't cure them this is not a reason for not benefiting from minimising exposure.

Spinal function and glutathione production is as or more important for MCS suffers than a reduction in ER exposure which is important but nobody tells them that and I've no idea how to prove it but at least Im thinking about it while recovering from ME which has more utility than telling them to just get on with it.

The end of back pain book by surgeon Patrick Roth will gradually fix anyone's spinal function with a kettle bell and exercise ball.

Diet and sleep will gradually fix glutathione production.

No one will make money from researching this so Dr's are forced to ask patients to just harden up. There's a lot of benefit in hardening up as well but it won't recover spinal function or increase glutathione production or decrease er or chemical sensitivity.

Here's the reason.

Serum ferritin is an accute phase reactant that elevates due to inflammation from acute and sometimes chronic illness or heritable genetic mutation.

When someone is ill and inflamed and fatigued and they have excess serum ferritin circulating in their blood which contains 4500 iron atoms per molecule and absorbs electromagnetic radiation it interferes with their biochemistry.

Why people scoff at investigating the prevalence of electromagnetic radiation exposure when there is a causative mechanism for elevated risk in sick people is because of either arrogance or ignorance. Maybe if the doctors listened to patients instead of diagnosing hypochondria when dealing with edge cases health outcomes would begin to actually you know improve.

This is Iranian research. So what. They have brilliant scientists. Serum ferritin absorbs and is affected by electromagnetic radiation and is highly elevated in sick people. As my serum ferritin has reduced from 1200 to under 310 through venesection and lifestyle I have gradually been able tolerate exposure to electromagnetic radiation without being fatigued by it for extended periods. People running a daily energy budget become pretty adept at working out what burns through their energy and electromagnetic radiation exposure definitely does and bored sick people definitely want to use wireless devices but can't. The hypochondria diagnosis is illogical when it comes to electrosensititivity.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3662108/

Against your one paper supporting the idea, there have been 100s of studies that do not. I’m all for science doing investigations, but we can’t accept a premise because it feels right.

What’s the fastest way to figure out the average existing fatigue levels and serum ferritin levels in the hundred studies so that I can quickly disprove my hypothesis?

I’m not saying it causes an illness I’m saying if you have a certain subset of illness it increases your fatigue. It also hurts your hands but you aint never gonna believe that ha ha. Iphone 7s are the worst.

I’m getting better and so is my tolerance to er so I’m not overly concerned about myself.

It’s the millions of other edge cases wrongly labelled as whingers by the medical system that I feel for.

ER doesn’t cause fatigue it exacerbates it in certain people. I better look at those hundreds of studies to figure out why I’m so wrong about this.

I don’t want to sell anyone a tinfoil hat or phone case and reducing exposure to er at night is great for sleep and CO2 emissions so why wouldn’t you.

Mercury in dental work works too!

Its not even funny how ignorant people are but let me rub it in: that one doesnt want to know there are biological effects has no more than placebo level effect. It is still an effect tho.

The "I'm not aware of any such research" should rule out any conclusion. Unawareness is only evidence of it self.

Personally im more worried about having my attentionspan cut into small chunks by endless notifications and having my sleep interupted.

I actually own the fancy rf measurment toys. Odly the most comfortable spot to sleep in the house also has the lowest measurments. Its sohh anecdotal, i know, i know..

> Turn your wifi off in your house at night and see if you sleep any better.

This needs to be a blind test, e.g. you track your sleep quality over a longer period of time while a script turns wifi off on random nights.

And you cover the green leds with tape mask, or get version with an accurate fake blinking patterns.

My ISP supplied router has an option to turn the lights off, which is great as otherwise it illuminates the whole hallway. I don't get why electronics makers think their product needs to have such bright lights.

The worst design is where the light is initially off but turns on when some condition arises (e.g. battery fully charged). You fall asleep in total darkness only to be woken up at 3am by the brilliant light of "your phone is charged now".

Simple. The engineers are working on the product during the day in well-lit spaces. Since the lights are always on, it never occurs to anyone that the LEDs might be too bright at night.

Alternatively, engineers point it out, and product managers don't listen

In a bright environment, a bright LED is useful. Instead they should also have a light sensor used to determine the ambient light level, and then adjust the status LED display accordingly. My Samsung TV does this with its "powered on" light.

Of course, that adds to the BOM and manufacturers love shaving off fractions of a penny. Asking them to add an extra 50 cents of parts for something consumers don't think about prior to purchase is a lost cause.

Old LEDs are fine in both bright and dark environments, too-bright LEDs are a recent (5y? 10y?) thing. I wonder if LCD could be even nicer... I don't think I've ever seen single-pixel LCD status indicator.

Any kind of light in my bedroom is deeply annoying to me when trying to sleep. And I have the same problem with sound too. Any kind of high pitch, etc, from a plug, light, etc, really does cause problems with my sleep.

> I don't think I've ever seen single-pixel LCD status indicator.

I approximate that by using a pin to poke a hole in the electrical or gaffer tape that I use to cover the lights.

It’s much easier to turn off the other lights than to brighten the environment enough not to see the blue lights of your router

In college, all of my electronics were in my bedroom as well as the communal router. I taped off as many LEDs as I could (even the router wall wart had a big blue light) and disconnected any LEDs that had leads (like inside a PC case). There were only a few instances of LEDs that I actually needed so those got white electrical tape over them to diffuse the light or swapped to red if the tape diffused it too much to see.

I don't mind having a nightlight on when I sleep, I think it helps me fall asleep quicker rather than pitch black but bright blue lights that fill the fucking room with light are the devil. I have much less electronics in my bedroom now since I now have personal space other than my bedroom to put stuff.

I've had a tiny chargeable buzzer that would light up entire rooms when it was plugged in. I started habitually closing the bathroom door just so it didn't bother me when trying to sleep.

I eventually got fed up that I broke the LED with some fingernail clippers. The device never turned on again.

I'm a pretty easy going person in life but learned how mad I could get over time at a pointlessly bright light and the people who put it there.

Does scientific rigor really seem like something the parent comment is concerned with?

And make sure that phones aren't getting messages and bleeping during the night when wifi is on.

When I was mining bitcoin I discovered graphics cards under load mess with my sleep, I would wake up feeling like I was very sick if I slept in the same room as a rig.

Noise, heat or blinking LEDs should be your first suspicions. Maybe transformer whine, with low quality power supplies. EM noise should be very low down your list of plausible causes.

You could just try it. Turn off the electrical stuff before you go to bed but hey everyone has freedom of choice.

Placebos work. If that's what you want, cool. If you want to figure out if RF affects sleep, that's cool too, but you'll need to double blind the experiment. Because placebos work.

Yes but so does human intuition and its a heck of a lot faster.

A healthy person can endure a toxic environment. An unhealthy person becomes more unhealthy from increased toxicity.

I’m not saying electromagnetic radiation makes a healthy person unwell i’m saying it delays or worsens recovery of some unhealthy people and there are million different subsets of unhealthy people so which subset are you going to run the double blind placebo on before you decide reduce electromagnetic radiation while you sleep.

It’s a simple experiment anyone can try. Two weeks of camping is an effective insomnia treatment as per research which eliminates electromagnetic radiation from the equation. I think its a zeitgeber in subsets sick people but there’s no profit in researching that so the only tools you have are existing research, intuition, self observation and logic.

People figure out how to sex chickens without a causative mechanism. It isn’t a placebo effect or a double blind trial. Electrochemical gradients as per Michael Levins research affect genetic expression. Much like hedging one’s bet by believing in a creator just in case reducing your exposure to RF at zero cost is the smartest thing someone can do with the available evidence.

Placebos in truth's clothing are toxins of human society. Please verify placebo vs truth before spreading, k? Thanks.

> Two weeks of camping is an effective insomnia treatment

Or two weeks away from the grind reduces stress. Or getting away from artificial lights/schedules reduces stress. Or it selects for people+times with less stressed. Or more healthy. Or higher SES. Or you're getting away from pollution. Or you need temperature variation to feel healthy. Or any two of those. Or three! Many plausible explanatory factors compete with RF, and you'd have to control for them in order to point the finger at RF. That's not impossible, and not even particularly difficult, but it does mean that you can't go on a camping trip, get better sleep, and then use that as proof that RF was to blame for your insomnia.

> People figure out how to sex chickens without a causative mechanism. It isn’t a placebo effect or a double blind trial.

The double blind trial is how you establish whether or not something is a placebo.

> Electrochemical gradients as per Michael Levins research affect genetic expression.

You need to blind you studies whether or not you have a plausible mechanistic explanation. You don't need a plausible mechanistic explanation to blind your studies.

> Much like hedging one’s bet by believing in a creator just in case

Which one(s)?

> reducing your exposure to RF at zero cost

Foregoing the advantages of technology is not zero cost. If you mean that turning your router off at night is zero cost, go ahead! I don't take issue with that.

I do take issue with spreading unblinded anecdata, because whether or not RF-induced-insomnia is real, RF-anxiety-induced-insomnia is definitely real, and anecdata like your own definetly spread it. If RF-induced-insomnia is real, that's for the best, but if what you experienced was a placebo (and I'd bet a substantial sum of money that it was), then unblinded anecdata literally are the problem. And that's not cool.

In the privacy of your own home: do what works and ignore the haters!

In society: please apply good experimental technique before causing anxiety in others. It's only polite.

I think you are uncomfortable that some phenomena particularly biological don't fit in a scientific experiment neatly and are more comfortable labelling 3% of the population hypochondriacs to alleviate your own anxiety.

What I've stated is that I experienced increased fatigue from exposure to ER while I was seriously ill and had elevated serum ferritin.

Each ferritin molecule has 4500 iron atoms and serrin ferritin increases with acute or chronic viral infections. A healthy level is less than fifty. So a 1150 times increase in iron atoms in someone's blood could plausibly cause fatigue when it absorbs er.

Who does this cause anxiety in exactly?

How is turning off electronic devices going to cause anxiety?

People can turn them off. If it helps great. If it doesn't don't bother.

No anxiety necessary.

You might be better educated than me, better connected than me and more intelligent but there's something to be said for original thought. I'd love to take you up on your bet where you impolitely just called me a whinger. I think I'm smarter than you are just sayin there wasn't one insightful thing in your comment as you tried to apply a method that doesn't really fit the situation. How do we do this? Let's bet our hacker News anonymous reputations on it.

Are you unfamiliar with how powerful the placebo effect is? Totally meaningless "treatments" can have real biological impacts, simply because the person receiving them believes it will.

If you truly cared about this topic, I assume you would want to know if the effect is real, or just your mind playing a trick on you.

> simply because the person receiving them believes it will

Perhaps somewhat bizarrely, maybe even if they know it's only placebo:

> In these four studies patients were randomised to receive open label placebo (pills described as "inert placebos containing no medication") plus usual treatment or usual treatment[...]

> The consistency and magnitude of symptomatic relief across these studies—performed in hospitals on two continents—suggest that open label placebo may have a real therapeutic benefit.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6889847/

> Yes but so does human intuition and its a heck of a lot faster.

It's also frequently incorrect.

Right, but you wouldn't know if your sleep improved because the wi-fi is off, or if it improved because you have greater peace of mind just knowing that the wi-fi is off.

These are different things. A blinded test would eliminate the peace of mind component and allow you to determine if there's a physical effect from the wi-fi being on or not.

Furthermore, if your peace of mind is the true reason why you sleep better with RF off, note that by talking of your experience you could actually be creating the problem that you were trying to solve (difficulty sleeping due to worrying about RF). If RF is really to blame as determined by a blinded test, it's worth talking about, but if not, please exercise restraint.

Sure, but you won’t learn much except how susceptible you are to the placebo effect.

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