Virtually all important technologies--fire, the wheel, the nail, the compass, optical lenses, paper, gunpowder, the printing press, the steam engine, the internal combustion engine, the telephone, electricity, automobiles, vaccination, airplanes, rockets, nuclear fission, computers, semiconductors or the internet--can be used for good or ill.
All have externalities--side effects--of varying impact, good and, or bad. All can be dangerous, even life threatening, to humans, animals, plants, property or the environment.
In the United States, 100 people die in auto accidents every day. The point is that virtually all technologies pose some risks. They must be used responsibly, carefully and with an understanding of trade offs.
And our understanding of the risks should be rational. In other words, we should base our understanding, to the extent possible, on science and transparent values (even if we do not agree on all the values, transparency at the very least is necessary to debate values).
Anything else is irrational. Consider the argument around the “safety of 5G.” Some of us, who have been in industries based on the use of radio frequency communications, are familiar with concern over non-ionizing radiation, the property of radio waves that can cause heat in human or other tissue. That is the same sort of radiation represented by sunlight, for example.
The issue is whether heavy does of non-ionizing radiation have adverse human health effects. Several caveats are in order, as always. To observe in any experiment any effect from non-ionizing radiation requires levels not found in nature, as with many other experiments related to human or animal health.
The other caveat is that, in addition to exposure levels, we cannot separate out the effects on non-ionizing radiation from all other potential health hazards in modern life. Even if a correlation of some sort were to be found, we could not rule out causation or correlation with some other facet of modern living.
At levels experienced by humans in real life, non-ionizing radiation has not been shown to cause harm, even minute heating effects. That is important. At sufficiently high power, such as in a microwave, non-ionizing radiation can definitely cause heating. The point is that such levels are not remotely close to anything found in RF communications.
The exception is worker safety for people who work directly on radio towers, for example. There it is reasonable to limit exposure. At the same time, it also is reasonable to point out that energy decay is logarithmic for non-ionizing radiation. Signals weaken very rapidly.
“To date, no adverse health effects have been established as being caused by mobile phone use,” says the World Health Organization. That might be worth reiterating, in light of concern in some quarters about whether 5G is “safe.” Keep in mind that power levels for cell phones and even cell towers are low.
Consider that a cell tower radio emits energy 100 to 5,000 times lower than a TV transmitter, for example. Some liken the power level to that of a light bulb.
Still, if you really are concerned about the possible health effects of using mobile phones, use them less. Text instead of holding the phone against your head and talking.
Radio signals weaken (attenuate) logarithmically, by powers of 10, so the power levels decay quite rapidly.
Basically, doubling the distance of a receiver from a transmitter means that the strength of the signal at that new location is 50 percent of its previous value. Just three meters from the antenna, a cell tower radio’s power density has dropped by an order of magnitude (10 times).
At 10 meters--perhaps to the base of the tower, power density is down two orders of magnitude. At 500 meters, a distance a human is using the signals, power density has dropped six orders of magnitude.
Using the internet on a smartphone, for example, puts the device a much-safer distance away from one’s head, in case your worry is possible health effects to the brain, as the phone is both a transmitter and a receiver.
Workers who climb cell towers, radio or TV transmission towers do have to take precautions against the high power levels emitted by such radios, as do other workers who regularly work around high-power sources.
But RF signals as encountered by consumers using phones, TVs and radios are quite low, as power levels drop sharply with distance, even the distance of your arm.
Physical objects also affect signal decay. Even for the low and middle-frequency radio signals used by cell phones, an office wall can reduce signals by 75 percent. A concrete wall can reduce signals by 94 percent. So physical barriers matter.
To be sure, it might always be impossible to assess long-term effects, as the sources of low level non-ionizing radiation occur naturally, from the sun, as well as from consumer devices. There simply is no way to conduct controlled experiments.
It might be good advice to recall that all technology use carries some risk, and that there always are ways to reduce risk, to obtain benefits. But we still must balance some level of risk. No technology is always and uniformly helpful.
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