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#213582 - 06/06/14 06:26 AM Measuring EMFs
schenimann Offline
Member

Registered: 02/18/08
Posts: 194
Loc: Western North Carolina
I had a customer call this week with possible EMF issues. Be warned that I am attempting to separate fact from perceived fact in reading about EMFs. He's been watching news and whatever else regarding these and decided to check out his home and office. He purchase an electromagnetic meter and was checking his office.

At the far corner where his desk is now he gets 3mg. As he moves closer to a particular wall it goes up to 100mg. He gets the same reading on both sides of the wall. He wants me to come and at least give an opinion about what may be going on. What in the world am I looking for and what would cause this? Is it an issue?

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#213583 - 06/06/14 09:31 AM Re: Measuring EMFs [Re: schenimann]
LarryC Offline
Member

Registered: 07/05/04
Posts: 775
Loc: Winchester, NH, US
I would suspect an electrical cable is going up the wall in that location where he is measuring 100 mg. If not electrical, then perhaps a magnetic object like a cast iron sewer pipe or a steel support beam.

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#213584 - 06/06/14 10:17 AM Re: Measuring EMFs [Re: schenimann]
gfretwell Offline

Member

Registered: 07/20/04
Posts: 9012
Loc: Estero,Fl,usa
I am not sure whether that is hazardous in any meaningful sense at all or just "gee Whiz" information but you could put on a show for him and isolate it by turning stuff off and see what seems to be creating the field.

You can certainly do invasive or non invasive investigations to see what is in that wall.
Just be sure the clock is running. wink
_________________________
Greg Fretwell

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#213586 - 06/06/14 02:37 PM Re: Measuring EMFs [Re: schenimann]
WESTUPLACE Offline
Member

Registered: 03/29/04
Posts: 252
Loc: Kingwood, TX USA
Do not get me started. I had a customer that bought one of these "testers" it was a homebrew box with some meter on it. Since it had no brand name no telling what it was calibrated to. She claimed her girl was exposed to excess EMF and cause her ADD. As she scanned the wall behind her bed the meter peaked (a 1" copper water line was in the wall) She wanted to know what to do. I suggested she move her bed to the other wall but she said it would upset the decorating style of the room. At that point I suggested she call a plumber to move the pipe at a great expense. She did not like that ether. Go figure.

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#213587 - 06/06/14 02:51 PM Re: Measuring EMFs [Re: schenimann]
gfretwell Offline

Member

Registered: 07/20/04
Posts: 9012
Loc: Estero,Fl,usa
A 1" pipe sounds like the entrance into the home. I suppose I would look to see where the ground clamp was (within 5' of the entrance point past that place in thew wall) and check the neutral connections.
If this is really a single conductor taking a significant amount of unbalanced neutral current to the street you would get a big field around it. Normally the pair of wires in a cable or raceway will cancel most of the field.
One conductor becomes an effective antenna.
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#213603 - 06/08/14 12:23 PM Re: Measuring EMFs [Re: schenimann]
WESTUPLACE Offline
Member

Registered: 03/29/04
Posts: 252
Loc: Kingwood, TX USA
The 1" copper was the water line (big house) The water service was PVC from the street. Bonding ground was made else ware. (garage attic) Electrical service was at the back of the garage, water line at the front. The problem is with the meter. Any piece of metal can become an incidental radiator. This may be EMF (Lo freq) or HF. The alarm system was connected (grounded) to the pipe. When I disconnected it from the pipe the detected "EMF" from the so called meter went down 60%, but the city manager (small town) said if the alarm system (12 V) was not grounded to the water pipe the house would catch fire! I gave up at that point and said to find another expert like the city manager to find the EMF problem.

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#213605 - 06/08/14 12:27 PM Re: Measuring EMFs [Re: schenimann]
gfretwell Offline

Member

Registered: 07/20/04
Posts: 9012
Loc: Estero,Fl,usa
I am not sure if it would make it better or worse but you could drive a rod next to the water service and bond that end of the pipe.
You might end up creating a problem where there was none before tho.
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Greg Fretwell

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#213606 - 06/08/14 12:56 PM Re: Measuring EMFs [Re: schenimann]
twh Offline
Member

Registered: 03/11/04
Posts: 892
Loc: Regina, Sask.
Here is a source for EMF meters: http://www.canadianghosthuntersupplies.ca/EMF-Meters-Devices_c_22.html

I wouldn't have thought a ground rod would do the same job as an exorcist. I learn something new every day!

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#213607 - 06/08/14 01:10 PM Re: Measuring EMFs [Re: schenimann]
WESTUPLACE Offline
Member

Registered: 03/29/04
Posts: 252
Loc: Kingwood, TX USA
Omega, extech and several other known test equipment co make gauss meters. If I was going in the business of looking for high EMF I would buy one of those. No ghost hunters site! This same customer blocked the cell phone co from putting a cell tower blocks from her home (on a water tower) now when she makes a cell phone call the phone inches from her head must put out full power to reach the next tower instead of 1/3 the power to reach the water tower. There are people reading stuff on this here internet and believing every word.

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#213609 - 06/08/14 08:31 PM Re: Measuring EMFs [Re: schenimann]
schenimann Offline
Member

Registered: 02/18/08
Posts: 194
Loc: Western North Carolina
I recently completed a rough in for a mbr/mba remodel. I actually installed a switch in the bedroom to kill all the power in the room. except for the switch and the sd. The HO was concerned about sleeping with the emfs. He also would not allow any osb because of the chemicals. Everything was no VOC if possible. Not sure if the cut off switch is code but it's in.

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