Live in 7 floor apartment building directly above electrical room for entire building and old elevator. Noticed static electricity or excessive charge and have been investigating. Measured EMF clocking in at around 78 Microtesla right above flooring.

What should I have an expert do to confirm? Is this dangerous? Can being above electric room spread EMF to unit?

And would my proximity to the electrical room at this field charge the metal in my unit? Faraday’s law? It would explain the excessive static electricity, no?

EDIT: Pro is coming to test EMF field and whether there is bad earthing/grounding.


closed as primarily opinion-based by winny, Finbarr, RoyC, jms, diverger Apr 17 at 5:58

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    \$\begingroup\$ Measured EMF clocking in at around 78 Microtesla right above flooring Which is in the order of magintude of the Earth's magnetic field. From Wikipedia: "The magnitude of the Earth's magnetic field at its surface ranges from 25 to 65 microteslas". \$\endgroup\$ – Bimpelrekkie Apr 15 at 11:05
  • \$\begingroup\$ I’m on the second floor. If that matters. So calling a pro to test with the right equipment is probably a waste of $500. \$\endgroup\$ – cascol33 Apr 15 at 11:13
  • \$\begingroup\$ This subject has been argued and researched for many many decades and you can find very many papers and opinions in both directions. | Note the several positive comments by people here and maybe follow up some refs along the lines that analogsystemsrf suggested. You'll find that your field levels are well below those that have cellular effects and well below MRI levels. | There is potentially just maybe some effects that are "in the noise" but if so, just by living sensibly you can vastly decrease your overall life risk factors in ways that utterly swamp any dangers that just maybe may exist.. \$\endgroup\$ – Russell McMahon Apr 15 at 12:16
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    \$\begingroup\$ Drink hot drinks cooler or never hot (less throat cancer), observe speed limits when driving (energy rises with V^2), drive with headlights on, don't carry cellphones in coat chest pockets (PROBABLY makes no difference. just perhaps maybe may), take the stairs, not the lift, look right-left-right when crossing road (or left-right-left in UK, NZ, Japan) or l r l r l r l ...... in China, India, ... . , etc etc etc . ie life has MANY risks. Sensible living will generally reduce overall life risks far more than dealing with those that are so uncertain as to be "in the noise" if they exist. \$\endgroup\$ – Russell McMahon Apr 15 at 12:21

What should I have an expert do to confirm? Is this dangerous?

An expert can only confirm that you correctly measured the 78 microtesla.

The World Health Organization estimates that the natural geomagnetic field is between 35 and 70 microtesla. 78 microtesla is higher than normal, but still unremarkable. When you're commuting in a (electric) train or working as a welder, you are exposed to fields that may be a thousand times larger. If magnetic fields were dangerous, you would expect welders, train drivers and plenty of others to die young. I'm not aware of significantly higher rates of cancer or other diseases for such professional groups.

The only known health issues at relatively low field intensities are:

For static electric fields, few studies have been carried out. The results to date suggest that the only acute effects are associated with body hair movement and discomfort from spark discharges. Chronic or delayed effects of static electric fields have not been properly investigated.

The same source mentions further effects like vertigo - but at 2 Tesla (= more than 10000 times the value that you measure).

Still, the absence of a proof of dangerousness is not the same as a proof of harmlessness:

It is not possible to determine whether there are any long-term health consequences even from exposure in the millitesla range because, to date, there are no well-conducted epidemiological or long-term animal studies. Thus the carcinogenicity of static magnetic fields to humans is not at present classifiable.

(Note that millitesla range is still at least a factor of ten higher.)

You're are certainly exposed to other environmental factors that constitute a much greater risk.

Can being above electric room spread EMF to unit?

You can shield electric fields and also high-frequent magnetic fields, but it's almost impossible to shield from static magnetic fields. You may at most deviate the field by some degree. So, the answer is "Yes", even if I wouldn't use the word spread in the context of static magnetic fields.

And would my proximity to the electrical room at this field charge the metal in my unit? Faraday’s law? It would explain the excessive static electricity, no?

Faraday's Law is (almost) irrelevant as it doesn't apply to static fields. I don't think that the static magnetic field has much to do with charging your metal items. Maybe transient / higher-frequent magnetic fields play a role, but I would look for other culprits first (faulty electrical installations, carpets,...)

  • \$\begingroup\$ Great answer, thanks. I am trying to diagnose why I feel jolts in my body when in the unit. A feeling as if I am accumulating electrons that have nowhere to go and ultimately are accumulating in my lower back and causing a slight "burning" sensation. I can feel almost like the ground is "moving" or sending discharges. I have a pro coming out to run the range of tests just to see what it might be. My thought was that the field from the electric closet or elevator power was charging major metal appliances and they were letting off ticks. I get 100 microtesla near the stove/fridge FWIW \$\endgroup\$ – cascol33 Apr 15 at 16:52

You are about 5 orders of magnitude (100000 fold) below the fields used in an MRI machine. These are the ones they're quite happy to use to image healthy people. Contrast this with Xray machines, where images are strictly only for the sick because of the health risks. You can totally forget it as a health issue.

In fact you should totally forget it as a health issue, because worrying about it could damage your health.

  • \$\begingroup\$ Any insight on why the EPA says things above 2millegausse is unsafe? I know this area spooks a lot of people resulting in snake oil salesman. I tested on an iPhone app. It was maxed out. Obviously that kind of freaks me out given problem I’d been having. Plus it’s 24 hour exposure. \$\endgroup\$ – cascol33 Apr 15 at 11:20
  • \$\begingroup\$ Go chat with a cellular-membrane biologist. Ask what field intensities are disruptive to ions moving back and forth thru the membranes. That is what matters. Or what field intensities will confuse the folding of proteins, in that the statistics of accurate DNA replication are altered. Knowing those field numbers may be comforting to you. \$\endgroup\$ – analogsystemsrf Apr 15 at 11:48
  • \$\begingroup\$ The sensor in an iPhone is designed specifically for sensing the geomagnetic field to act as a compass. "Maxed out" is about 1mT. \$\endgroup\$ – Phil G Apr 15 at 15:10

The safe magnetic limits for MRI technicians are several orders of magnitude higher, beyond the level that small magnetic objects start flying about.

Magnetic fields from equipment aren't dangerous. Normal levels of EMI aren't dangerous; if you were to measure the radio emissions in that room, you'd probably find the most powerful emitter was the iPhone itself when talking to the cell tower.

What might be dangerous and producing "tingling" when touching metal is good old fashioned electrical safety issues - bad earthing, for example. Or the small but catastrophic risk of fires.

  • \$\begingroup\$ How can one determine bad earthing? Landlord is trying to protect themselves from a major rewire and try to block access to my Independent expert. Would inspector need access to electric room? Could it be determined from my unit. Thank you! \$\endgroup\$ – cascol33 Apr 15 at 12:01
  • \$\begingroup\$ Suppose that "room" has 2,000 volt wiring to stepdown transformers, and also to run the elevator. And 0.5 meter above that wiring is a metal bedframe. To greatly reduce the electric field coupling, place chicken wire under the rug, and ground that chicken wire. To greatly reduce the magnetic field coupling, place steel sheets under the rug; the high relative MU of steel/iron lets you use thin sheets. Were you to attempt magnetic shielding with copper (MUr = 1), you'd need 1/2" thick copper plates for any benefit.. So use steel, and ground it, shunting electric-field-induced sparking. IMHO \$\endgroup\$ – analogsystemsrf Apr 15 at 12:44

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