It is not unusual to watch a flimflam walk into a city council meeting with all the earmarks of a hoax. He will be followed by a number of hysteric ranters, frightened for your children and making the audience feel stupid because they can’t understand the strange manner in which they are catenating scientific terms. A problem with this approach to public policy is the media gets bent out of shape after hearing only one side of the story. One rule of thumb for detecting a hoax is to ignore hype. If facts are true, they will be true in calmer moments when objective analysis is possible. For the record, the speakers Tuesday, who feared electromagnetism would cause childhood leukemia, were more educated than most.
Another is to get a grip on science. Science is the art of disproving. For example, a scientist tasked with proving unicorns do not exist will surely fail until he has searched every square inch of the universe simultaneously. Therefore, no credible report proving EM does not cause childhood leukemia will ever be forthcoming. Another consideration is causality. Just because a study of 26 children with leukemia found all 26 had noses, is no reason to take a nose for a risk indicator.
Links between childhood leukemia and residential proximity to power lines have been found and not found in studies since 1979. To try to settle the matter, an act of Congress created the Electric and Magnetic Fields Research and public Information Dissemination program as part of the Energy Policy Act of 1992. The American Physical Society in 1995 and the National Academy of Sciences National Research Council in 1999 both concluded there was no evidence for the alarm. Subsequent studies have only identified “weak,” “very weak,” or “potential” correlations.
In addition to the testing phase, the scientific method also involves theory. The predictive powers of an attempt to describe why an event occurs, by looking for overarching patterns, is then put to the test with experiment, the outcome of which is used to refine the theory for more experimentation, and so on. It is therefore instructive to look at what happens at a substation.
Substations typically employ transformers to scale-down voltage. High voltages generated at Lake Julian are efficiently transmitted through power lines to the substation, where voltages are lowered for distribution to homes and businesses. In the old days, this was done with transformers, which are nothing more than coils of wire with different numbers of windings.
Misconceptions about voltage have prevailed through the years. Potential is created by loading a mass with extra electrons. The mutually-repulsive electrons, of course, will be looking for an exit ASAP. Air is a very good insulator, but sometimes conductors are wrapped in insulating materials to make it harder for the electrons to bolt. Any operating substation that is not throwing sparks is sufficiently insulated. The problem comes when kids hop the tall fences and touch two objects of vastly different potential, providing a path for electrons to discharge through their heart. As students of AB Tech’s electrical engineering program used to say ad nauseam, “It’s not the voltage, but the current that kills you.”
Having hopefully established that voltages do not leap over substation fences to attack, we now turn our attention to the electromagnetic fields. All matter has an electric as well as a gravitational field. We often do not see evidence of the electric field because positive and negative charges are normally, for all intents and purposes, equally paired. When they are not, we see cool magic tricks. We get shocks when a small number of electrons rush to equalize charge. The world of chemistry is based on neutralizing charges.
When an electric field changes, an electromagnetic field is created. All of radio science is based on the idea of using antennas to oscillate charge, reshape the ambient electromagnetic field, and transmit signals. Substations in the United States deal with 60 Hz mains power. A paper put out by the Environmental Health & Safety department at the University of California – Irvine, put this in perspective. “Microwave ovens produce electromagnetic energy with a wavelength of about 5 inches; microwaves have enough energy to cause heating in foods. X-rays, which have wavelengths of the order of one-billionth of an inch, have enough energy to break atomic and molecular bonds. In comparison, a power frequency field at 60 Hz has a wavelength of more than 3000 miles – about the distance from Los Angeles to New York!” Cell phones, radios, and TV’s produce higher-frequency fields than those handled by substations.
George Hathaway, an electrical engineer of no small repute for his expertise in the proper handling of instrumentation, was contacted for this article. His labs, located in Toronto, now concentrate only on debunking claims nobody else seems to be able to figure out. Hathaway was hesitant to comment without knowing a host of variables about the structure. Typically, the EM field would be small, decreasing as the square of distance from the source; the electrical field would be stopped at the fence OSHA requires to be grounded; and any magnetic effects would be shielded to the point they wouldn’t interfere with the operation of appliances, such as making computer screens jitter.
As a substitute to calculations, he recommended renting a Gaussmeter and walking around a similar substation, taking readings inside nearby buildings. He also recommended setting up a Gaussmeter to take readings hour by hour. Erring on the side of caution, he said if the simulated exposures to children would be above 2-5 milliGauss, he would recommend reinforcing the shielding at the substation, metal sheeting being adequate. He then added, “I highly doubt that the field from a substation would compare to the 60 Hz fields from nearby appliances, such as TV’s, monitors, etc. in the school itself.”
A friend of a friend who works for Duke, who wished to remain off the record, agreed smartphones were likely a greater hazard. He explained, “You’re never going to win with these folks due to their Postmodern philosophy. It’s not about facts, but it’s about how they feel about perceived facts. No logic. Long-term effects of EMF, radiation, etc. are always debatable.”