High AC Magnetic Field Readings (3-4 mG) in Texas Home Master Bedroom and Backyard

Apologize in advance for the long post! We are in this particular situation and, being a novice with electrical- related issues, would greatly appreciate opinions here.

After a year long search, we found this nice home in Texas meeting all requirements my wife and I were looking for, and at the right price! We entered the option period and the home inspection went good. In the meantime, we also had a radon inspector look at the home - and since he also did EMF inspections, we added that too to our inspection list.

The radon results were good but EMF inspections revealed generally elevated AC power related magnetic fields in the home & backyard. Most of the home showed 1.2 to 1.8 mGauss (0.12-0.18 microTesla), which though a little higher than typical, is still ok. The problem is that the first floor master bedroom and the porch/ backyard, which are situated towards the west side & back of this N-S oriented house, showed EMF up to 3-4 mG levels (an overview pic is attached). I know there is debate about what the safe levels are for chronic exposure, and that there are no legal mandates, but many healthcare panels recommend residential exposure below 3mG, preferably below 2.

The magnetic fields are actually much higher at the east, south and west perimeters of the home, presumably from the power feeds running underneath the property lines (to this home and neighbors), but they fall off rapidly to

This is a matter of your life and it's quality. So, my advise is to not let concerns of "indelicacy" stop you. Simply explain your motives/concerns and if they grant you access [which is likely, since it's more probable their agenda is to sell the house, than to manage decorum] then do your tests.

One test might be to use a beefy jumper cable (perhaps one for jumping a car battery) to reconnect that grounding wire to the grounding rod. But, use extreme caution: that wire might be hot, so wear insulating gloves [you can get them at most hardware stores -- make sure they are specifically electricians gloves and that the insulation is rated for voltages at least twice what is present on that property--don't know what part of the world you're in ].

And just to be sure, regarding my suggestion to use a jumper cable to reconnect that ground line: I mean that to be a temporary condition for TESTING PURPOSES ONLY. Before the house is occupied, an electrician should be called in to properly connect that line.

Just wanted to make sure that was clear.

F Fran - I personally don't like any EMFs in my living space; those especially where I spend lots of time. I have taken this to the point of minimizing WiFi connections and replacing them with a hard wire. There is so much stuff in the literature of the alternative scientific paradigm which suggests that EMFs can play an important role in both health and illness. Seems that back in the 70's there were clusters of childhood leukemias associated with HV transmission lines. They were later "proven" to have no effect. With the choice between big-business power producers and moving their towers, I think it was a matter of finding a profitable solution. If you want to discuss this, let's do it Off-Line (pun intended) at salama(_at_)msala.us . Martin

Or, you can click on the "MARTIN SALA" link, above, and on the page that appears, click the "Contact" tab. Then you will be presented with a secure contact form

Steve, Thank you! Martin

Thanks Steve for your response. I think you make a valid point about overlooking the indelicacy part!

It is just that the parting was disappointing to the seller as they had been informed things looked good on the regular home inspection. They have never heard of EMF inspections and I think they felt this was a flimsy reason to not buy a home.

Btw, do you have an opinion on my Q, i.e., what are the odds - with the above magnetic field profile of the home- the cause is related to wiring / grounding problems within the home (versus, coming from the utility's underground power feeds to the adjacent homes)? Thanks.

Thanks Martin.

I am in the healthcare field myself, and sensitive to these issues. There are things in our environment that are contributing to increased chronic disease load, and these have not been fully understood or characterized. And there is a tendency by businesses and governments to rush to term these harmless. I do now want to, at least knowingly, increase my exposure to such factors.

What I am trying to understand in this particular situation is if wiring/grounding issues (i.e. potentially fixable) may be causing the increased magnetic fields, or if that is extremely unlikely?

Well, this is outside my field [I take no credit for the pun ;] so I can't really advise. So the following are slightly educated guesses [and I offer them only to "stir the pot" and maybe get someone else to chime in and either correct me, or elaborate]. And to make this discussion easier, I shall designate the house you like as *House A* and the "Plan B" house as *House B*

* It's possible that if the ground wire is not actually grounded, this may allow the house wiring to act as an antenna and cause the high EMF readings you were seeing.

* Perhaps there is an underground distribution transformer that is closer to *House A* and further from *House B*.

* It may be that the line is closer to the surface under *House A* than *House B* or the earth may be more conductive at *House B* and thus is acting more like a Faraday Cage. A Faraday Cage is a box made of some form of conductive material, usually Copper, or Copper plated metal. The conductive material absorbs electromagnetic energy and thus prevents most or all of it from entering the box (or cage). This is used by engineers to create a "quite" zone where RF testing or research can be performed without exterior interference. The Earth has various degrees of conductivity, depending on various factors like salinity, water content, iron content, and I'm sure other things that I'm not aware of. The more conductive the ground is around the transmission cable(s) the more it will absorb EMF. BUT [and this is where I _really_ lack in knowledge] it seems to me that the ground could also act as a "parasitic [or passive] radiator" and thus re-radiate some of the energy. But, considering that the wavelength of a 60Hz signal is 500 km (or around 3000 miles!), it doesn't seem like this would happen, but who knows, maybe just enough to bump the fields up to what you were reading.

But, this is all speculation from someone that studied RF in school but never pursued it as a career, or even as a hobby (though, in my youth, I did achieve both a 2nd class radio-telephone license and a novice amateur radio license, but that was nearly 40 years ago).

Thanks.

Those are all very good points you make.

F Fran - For a magnetic field to be generated in a conductor (a wire) then current or power must be drawn through it. This load would need to be something big like pumps, A/C unit, air handler, dehumidifier, freezer, frig, arc welder (although you'd probably notice this!), electric heating and so on.

I would recommend you do a magnetic survey again, keeping close notes of where the fields are high. Then locate the MAIN power panel and switch the MAIN circuit breaker OFF. Redo the survey. If the results are the same, the issue lies outside of the house. If they are different, you need to discover what is consuming the power, drawing current and inducing a magnetic field.

If you want to carry on this discussion, go to my website email (msaladotus)

Good luck,

Martin Sala, engineering physicist

Hi f fran.
I am very surprised at the number of people who are concerned about these fields. Although it would be pleasing if the higher frequency ones weren't present in sufficient strength to wipe put broadcast band frequencies. There is scant attention paid to this with new things such as LED lighting etc. Thus it is good to see discussion on it. However I in my own life I have worked in several broadcast stations of 50kW, and one of 1MW. The 50kW stations have coupling huts wherein I could hold up a fluorescent tube anywhere and they would light. Touching the telephone metal parts (old black bakelite phone) would give me a nasty little RF burn. I believed that I could also "Feel" the presence of the RF. Others could as well. These levels would be unacceptable these days, but I still work in very strong RF fields close to 100 watt mobile transceivers. I believe that no harm has befallen me in my 45 yrs of working with RF. Personally I would ignore totally any such concerns in a residential area. I would have no hesitation whatsoever to move in to your first selected home. If I was into restoration of vintage AM radio sets (which I am) and the house had enough RFI to foul up the broadcasts and I could not correct it I would think about not moving in, but that is about it. Before I go, I have an internationally patented invention which is intended to stop electromagnetic fields from escaping their source. Little interest has been shown in it to date. Industry does not want to change and will not until forced to do so. Look at GM, went nearly broke because of this. You can see a spectacular video of my invention on www.mulpin.com Cheers from Rod.

Interesting. I noticed that the "conventional" PCB was placed on the Tesla testing stand with the components face up, where as the Mulpin PCB either had no components or the components were face down. Not that it means anything, just interesting.

Actually, I took another look and there are no visible components other than two rectangular things that look like headers. The video never really gives us a good look at the thing. Nor is there any narrative or anything that explains why the two types of circuit board are so different.

Also, it's more likely the components on the conventional PCB were damaged rather than the PCB it self. But, once again, no close ups.

Hi Steve. We did the best we could with available time here. The Mulpin PCB has all of its parts buried inside the PCB except for the headders.
Having problems convincing the site that I enter the code correctly but it refuses to allow me to comment. Third time lucky maybe!