In the ninth grade I was in chorus for a few months until the instructor offered me an “A” for the rest of the year if I dropped her class. True story. You would think a guy who likes music but can’t sing would at least enjoy humming, but that depends. Research has shown that humming can cause anxiety, depression, insomnia, and in some cases, ghosts. Also true — though of course I left out a few details there.

Humming to a song because you don’t know (or can’t sing) the words is harmless, unless maybe it is incessant and happens to irritate your co-workers. But many industrial processes like blast furnaces, cooling towers, and giant compressors and vacuum pumps can emit low-frequency or infrasound hums able to travel tens of miles. Because human-caused hums have unusually long wavelengths — in some cases more than a mile — the hum can travel easily over mountains and through buildings.

Nature can produce these types of sound waves during events like avalanches, earthquakes, and volcanic eruptions. Wind of a particular speed and direction blowing through a canyon can make infrasound. And certain animals, most notably whales and elephants, communicate long distances in this way. Fortunately, natural hums are more transient and less disruptive to us than those of mechanical origin.

Infrasound is sound consisting of waves less than 20 cycles per second or Hertz (Hz), which might also be the standard unit of payment for car rentals, I think. It is estimated that only about 2% to 3% of the population can hear sound at this level. Most humans are able to hear in the range of 20 to 20,000 Hz. Above that is ultrasound, like the kind of waves used in medical scans.

Besides the fact that infrasound can invade our homes on a 24-7 basis, one of the big problems is that we tend to feel it more than hear it. By definition, sound is a series of pressure waves that make subtle changes in the air pressure at our eardrum. The eardrum vibrates in response to pressure fluctuations, which the brain then interprets as sound. The thing is, waves which alter air pressure will vibrate our eardrum even if the movement is too slow to be recognized as sound. This is why infrasound can cause dizziness, vertigo, nausea, and sleep disturbance.

But our eardrum is not the only part of us which vibrates to low-frequency sound waves. All human organs have what is called a “mechanical resonant frequency,” which is the wavelength that will cause tissue to slightly wobble on its own. Human experiments found that cardiac effects occur at 17 Hz; subjects reported feelings of terror, impending doom, and anxiety. And in a 1976 study, NASA determined that the human eyeball resonates at a wavelength of 18 Hertz.

Which is where ghosts come in. Or at least a discussion thereof. In 1998, a British researcher named Vic Tandy published a paper called “Ghosts in the Machine” in the Journal of the Society for Psychical Research. At some point he began to feel a sense of dread, and then to occasionally see gray, blob-like apparitions, while working alone in his medical-equipment lab. One day he clamped a fencing foil in a vise at the lab to work on it, and the foil began to vibrate wildly. He found that a recently installed vent fan was vibrating at exactly 18.98 Hz. When it was switched off, the foil stopped vibrating, and he felt better and stopped seeing objects in his peripheral vision. Since then, repeated experiments have produced the same visual anomalies.

One of the best-known cases of infrasound in the environment is the so-called “Windsor Hum” in the Windsor, Ontario region, which the Canadian government has traced to a US Steel facility on an island in the Detroit River. This low-frequency, 35-Hertz hum is said to be louder than ever since resuming in late 2017 after a brief hiatus. Since the hum began in 2011, there have been reports of some residents moving away to escape its debilitating effects, which include insomnia and nausea. In 2012, more than 20,000 city residents joined a live teleconference to complain about the situation. Sadly, US Steel has rebuffed all attempts by Canadian authorities to meet with them to try and fix the problem.

Knowingly causing such large numbers of people to suffer that long for personal financial gain constitutes an especially heinous crime. Unlike the case with war crimes and genocide, the concept of Crimes Against Humanity does not have to be connected to armed conflict, although its definition varies by country. The UN began the process of codifying it in 2014. One current statute defines it as any “…inhumane acts intentionally causing great suffering, or serious injury to body or to mental or physical health.” No person or corporation should be allowed to hold people’s wellbeing hostage.

In northern NY State, I have perceived a similar hum over the past 15 or so years. Although it varies in its intensity, I have heard it equally loud from Gouverneur to Canton to Massena. My road has no electric service, so I have no home appliances to potentially cause it. More noticeable at night, it does sometimes shut off. In late November 2018 it began again after a break, and is particularly strong at the moment.

Feel free to share your experience with infrasound hum at ph59@cornell.edu. If you feel such a thing is having a negative impact on your health, I encourage you to contact your elected officials.

Photo of frequency range of human voices courtesy Cornell University.