I'm pointing to this above website, because it's coming around to that time of the year again when most of us in the northern hemisphere will be spending more time indoors, and if your home is underneath or near one of our high voltage power lines, you may be interested in some of the information provided by the nation's original experts on radiation.
Periodically, some self-styled 'expert' (being defined as 'anyone more than ten miles from home') shows up, trying to convince us that our cell phones are killing our brain cells with their radiation, or that our kids are in danger of being cancer victims because their school playground is partly beneath the electric company's high voltage power lines.
So before some huckster induces panic in your already stressful life, may I please suggest that you bookmark the above website for HPS.org?
Briefly, or as briefly as I can manage, here's the poop: Cancer-producing radiation has to be radiation of a certain range of high frequencies, such as those found in microwave ovens, radar equipment, and similar high frequency or ultra high frequency devices, also including natural radiation from sources like our sun with its various thermonuclear radiation types.
You can't get cancer from exposure to radiation from that nearby power line.
Why not? Because: the frequency of it is only 60 cycles per second, which is rated as 'ultra-low frequency' on the internationally accepted rating scale.
Also, air being a very good insulator, and those lines being many feet above anyone's head, and that frequency being ultra-low, and the voltage, even at let's say 500 Kv, or 500,000 volts, being insufficient to produce a significant radiation field beyond the limits of safe approach, which, in this case is listed as being 7 meters, or 22.98 feet. So, for example, if that 500 Kv line is mounted on 90-foot towers, there's still 67 feet between you on the ground and the nearest limit of safe approach to that 'hot' or 'live' conductor, and you have
absolutely nothing to fear from its radiation.
"But", you say, "I've seen little blue lightning-like emissions and heard hissing noises with those, around the hardware of those high voltage conductors, so what about that?" That is called 'corona' and is caused by the high voltage of the conductor's electrical field around the cable stressing the surrounding air's
insulating value, and overcoming that insulating value of the air for a few inches next to the conductor at points on the hardware where those voltage stresses are greatest, such as at sharp corners of the hardware, or on fasteners like bolts that may not have been adequately designed with rounded surfaces to distribute those voltage stresses more evenly. So if you see 'corona' after dark at certain places along a high voltage line, you know the hardware wasn't made to reduce or eliminate that effect. And that 'corona' effect is part of normal line losses during transmission of the energy, and it can amount to as much as ten percent of the total output of the system. So it's not an insignificant consideration in the design of a system. Modern systems have specially designed hardware with smoothly rounded surfaces to more evenly stress the surrounding insulating air, to reduce this 'corona' effect, but there will be some, especially at switching points. But you can't get cancer from that either.
"How do you know?" you ask. I know because from the 23rd of August, 1950 until the 31st of March, 1988, I worked closely with an electric company's power distribution and production systems, with equipment up to and including 500,000 volts, and sometimes, that included being inside the safe limits of approach as outlined in the rule books, and I didn't get cancer from it. So if I didn't get cancer while working on the equipment, you aren't likely to, just living nearby. And I hope this clears that up for you. But do read what they say on HPS.org for more details. And leave me a comment with any questions, please.
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