What wiring method can be used to limit EMF in a home where people can "feel" EMF?

Status
Not open for further replies.

junkhound

Senior Member
Location
Renton, WA
Occupation
EE, power electronics specialty
Actually ran into a block trying to find historical info on the web to quantify signal strength for folks here.


Could not find the wattage of WCVS in the 1950s, call sign has reverted to an FM station.
WCVS was originally WCBS in Springfield IL, 1926 license, changed to WCVS when the CBS flagship station in NYC wanted that call sign.

The transmitter was only about 2 mi from our house, and 60+ years later cannot remember the wattage then, but thought it was 20kW (area AM stations now only 1 kW).

The mention of galena also brings back memories of being able to get all 3 of the local AM stations with just a chunk of coal from the mine down the street, a safety pin, and a few yards of whatever wire we could find, and a pair of 50 cent 2kohm impedance army surplus headphones.

Bust up a chunk of the high sulphur central IL coal and us kids got a few chunks of gold (pyrite) and silver (galena). Stretch a coil of wire to different lengths on a paper towel tube, hook up to a safety pin and the chunk of galena and the headphones, play around with the wire coil and the safety pin until ya got the station you wanted (sometimes took us kids an hour or so).

Ah, the good old days...a few years before that no building codes yet, when grandpa wired the house in 1914, he pulled tarred cotton covered 14g thru the old gas pipes - the 'fuse box' was an asbestos lined section between wall studs with a piece of solder as the fuse. Never ever had any house fires in the area either.
 

GoldDigger

Moderator
Staff member
Location
Placerville, CA, USA
Occupation
Retired PV System Designer
Actually ran into a block trying to find historical info on the web to quantify signal strength for folks here.


Could not find the wattage of WCVS in the 1950s, call sign has reverted to an FM station.
WCVS was originally WCBS in Springfield IL, 1926 license, changed to WCVS when the CBS flagship station in NYC wanted that call sign.

The transmitter was only about 2 mi from our house, and 60+ years later cannot remember the wattage then, but thought it was 20kW (area AM stations now only 1 kW).

The mention of galena also brings back memories of being able to get all 3 of the local AM stations with just a chunk of coal from the mine down the street, a safety pin, and a few yards of whatever wire we could find, and a pair of 50 cent 2kohm impedance army surplus headphones.

Bust up a chunk of the high sulphur central IL coal and us kids got a few chunks of gold (pyrite) and silver (galena). Stretch a coil of wire to different lengths on a paper towel tube, hook up to a safety pin and the chunk of galena and the headphones, play around with the wire coil and the safety pin until ya got the station you wanted (sometimes took us kids an hour or so).

Ah, the good old days...a few years before that no building codes yet, when grandpa wired the house in 1914, he pulled tarred cotton covered 14g thru the old gas pipes - the 'fuse box' was an asbestos lined section between wall studs with a piece of solder as the fuse. Never ever had any house fires in the area either.
I like that fuse design. Since the heating came as much from the wire as from current through the solder, it automatically adjusted to the ampacity of the wire.
:)
 

Rampage_Rick

Senior Member
Well as I am told emf above 10 Gauss is detrimental to health.
Just where pray-tell did you find that nugget 'o wisdom? First of all, most pacemakers are certified to operate normally in a 10 Gauss field. Secondly, MRI machines operate in the 5,000 - 30,000 Gauss range, and I don't see any imaging technicians dropping dead. Certain research MRI machines can hit 100,000 Gauss (10 Tesla) and there's one that can do 117,500 Gauss. Heck, the tiny rare-earth magnets inside each and every computer hard drive are about 10,000 Gauss (excluding SSDs of course)

Now compare this to people wandering around with a hand scanner getting upset about a few milligauss. Every time I hear the made up word "electrosmog" I want to punch myself in the face.
 

mbrooke

Batteries Included
Location
United States
Occupation
Technician
Just where pray-tell did you find that nugget 'o wisdom? First of all, most pacemakers are certified to operate normally in a 10 Gauss field. Secondly, MRI machines operate in the 5,000 - 30,000 Gauss range, and I don't see any imaging technicians dropping dead. Certain research MRI machines can hit 100,000 Gauss (10 Tesla) and there's one that can do 117,500 Gauss. Heck, the tiny rare-earth magnets inside each and every computer hard drive are about 10,000 Gauss (excluding SSDs of course)

Now compare this to people wandering around with a hand scanner getting upset about a few milligauss. Every time I hear the made up word "electrosmog" I want to punch myself in the face.


Big difference. One is a constant DC field, the other (like power systems) is an alternating field. Alternating fields (AC power) was only chosen over DC for one reason: Magnetic induction. The basis of power transformers and induction motors. Without these 2 assets electrification might never have been practical.

And while fields of 10,000 gauss may not instantaneously harms a person (like drinking liquid Mercury {HG}), the long duration 24/7 exposure is what matters. The mercury will pass right through a colon, and gastrointestinal absorption via single time event will not put anything significant into the body; thus I can declare Mercury none toxic. However if I did that at every meal, or stood next to vials of open mercury for years on end, the mercury would billed up in my system and then I would start to notice.

But who would say Mercury is to blame? If the long terms effects are never documented, called a conspiracy or scrubbed from medical literature (all it takes are a few perceived authority figures to say so); symptoms like tremors, muscle spasms, skin bleeding, hair loss, memory impairments, hair loss, irritability, ect ect, even death might be called a disease or even normal aging if the poisoning is milder.

But none the less Mercury is still one of the most toxic elements (and perhaps substances) that can be found.

Further more, proving mercury is poisonous can be difficult because exposure, absorption method, amount, duration, age, health and even type of mercury compound play a huge role to how any individual person will respond.

Get the picture?

Keep in mind that if I traveled back in time and said lead, mercury and arsenic are slow accumulating neuro toxins Id be declared a nut. If I went in time a tad latter to the 60s and said asbestos will one day be removed in space suits while mesothelioma lawsuits fly, Id be laughed at. Experts would say Im delusional while media would portray be as an unstable character who paints himself self as a stripped clown who believes the anti Christ is in every object that has a 3, 5 or 8 letter name. Of course that isn't true, but because the media says so any mention of asbestos being toxic turns into "yup, its one of those anti Christ space alien believing crackpots"

Exaggerated yes, but that's pretty much how it all works in a nut shell.



Anyway, the mercury absorption link for those who think Mercury is easily absorbed when swallowed:


http://www.heracliteanriver.com/?p=246
 

FionaZuppa

Senior Member
Location
AZ
Occupation
Part Time Electrician (semi retired, old) - EE retired.
i am not sure if the OP is asking about magnetic fields from an "on" device, or the EMF you get when you turn off light switch and the small spark creates EMF. the faster something turns off the stronger the mag pulse is.

for mag fields you can control them with mu
http://en.wikipedia.org/wiki/Mu-metal

i would be interested in knowing how much mu the US govt has purchased over the years, especially in cold war times....


wrap your knoggin in mu ;), or find special wire that has mu foil in it, or wrap the wire yourself at install time.
Joaquin-Phoenix-source_IGN.com_.jpg
 
Last edited:

Rampage_Rick

Senior Member
Big difference. One is a constant DC field, the other (like power systems) is an alternating field. Alternating fields (AC power) was only chosen over DC for one reason: Magnetic induction. The basis of power transformers and induction motors. Without these 2 assets electrification might never have been practical.
That only holds if you never move. Yes a fixed magnet or DC powered electromagnet will have a static magnetic field, however the field is not uniform. As soon as you start moving around in the field you're now being subjected to varying intensity, which is the same mechanism that allows you to induce a current on a piece of wire by moving it in relation to a magnet. Please explain how one varying magnetic field is harmless yet another varying magnetic field is harmful?

If a 60 Hz magnetic field is harmful, would it also be harmful to spin a bar magnet at 3600 RPM?

magnetic-fields-in-action.jpg
 

Rampage_Rick

Senior Member
Regarding the rest of your post, there's one significant difference between EMFs and mercury, asbestos, etc: Observable occupational health effects.

Asbestos: Health effects first noticed in 1899. First documented death in 1906. Massive number of worker deaths observed between 1900-1910. There were significant health concerns by the 1920-1930s. Your point that you'd be laughed at in the '60s is absurd. It was a known but accepted hazard.

Mercury: Health effects observed for centuries ("mad as a hatter") Medical reports published in 1823, possibly earlier. Significant study between 1923-1926. A known but accepted hazard.

Conversely, EMF has been studied upside-down and backwards for the better part of four decades, and there's still no proof of harm.

Regarding cellphones and cancer: If there was an effect, we'd expect to see a spike in brain tumors that coincides with the introduction of phones, and a marked decrease that coincides with the introduction of smart phones (a significant portion of use switched from beside the head to in front of the body) I've yet to see evidence of the first spike.
 
Last edited:

GoldDigger

Moderator
Staff member
Location
Placerville, CA, USA
Occupation
Retired PV System Designer
There are studies which show that some EMF sensitive people can defect very accurately whether the interviewer thinks the field is on. Not so much whether the field is actually on or off. So valid experiments need to be double blind by design.
 

mirawho

Senior Member
Location
Sun Valley, CA
There are some electrical lines running down the side of my property next to my house. I assume they are medium voltage. I don't know if they affect me adversely but they definitely affected my old CRT televisions, and my single coil guitar pickups howl at 60hz if I hold the guitar parallel to the direction the lines run with gain way up on my amp.
Electro-Harmonix Hum Debugger!
 

FionaZuppa

Senior Member
Location
AZ
Occupation
Part Time Electrician (semi retired, old) - EE retired.
Regarding the rest of your post, there's one significant difference between EMFs and mercury, asbestos, etc: Observable occupational health effects.

Asbestos: Health effects first noticed in 1899. First documented death in 1906. Massive number of worker deaths observed between 1900-1910. There were significant health concerns by the 1920-1930s. Your point that you'd be laughed at in the '60s is absurd. It was a known but accepted hazard.

Mercury: Health effects observed for centuries ("mad as a hatter") Medical reports published in 1823, possibly earlier. Significant study between 1923-1926. A known but accepted hazard.

Conversely, EMF has been studied upside-down and backwards for the better part of four decades, and there's still no proof of harm.

Regarding cellphones and cancer: If there was an effect, we'd expect to see a spike in brain tumors that coincides with the introduction of phones, and a marked decrease that coincides with the introduction of smart phones (a significant portion of use switched from beside the head to in front of the body) I've yet to see evidence of the first spike.

well, we cant stand in front of 10k watt FM antenna now can we...... why?
continuous low dose rates can harm people.
the man-made stuff is typically bad no matter how you slice-dice it.
 

mbrooke

Batteries Included
Location
United States
Occupation
Technician
That only holds if you never move. Yes a fixed magnet or DC powered electromagnet will have a static magnetic field, however the field is not uniform. As soon as you start moving around in the field you're now being subjected to varying intensity, which is the same mechanism that allows you to induce a current on a piece of wire by moving it in relation to a magnet. Please explain how one varying magnetic field is harmless yet another varying magnetic field is harmful?

If a 60 Hz magnetic field is harmful, would it also be harmful to spin a bar magnet at 3600 RPM?

magnetic-fields-in-action.jpg


Because one magnetic field isn't variable in the same way as the other. Most people don't sit next to spinning magnets, and a 60hz field rises and falls changing direction, not the same as standing next to a magnet going back and fourth. Further, a spinning magnet (at least your average one) isn't capable of heating up ferror magnetic conduit like if you were to only carry current through one and not both conductors in a conduit.


And yes, the earth is the biggest magnet, however does a loop of copper in the earths field begin to generate voltage and current at the surface level?
 

junkhound

Senior Member
Location
Renton, WA
Occupation
EE, power electronics specialty
however does a loop of copper in the earths field begin to generate voltage and current at the surface level

Yep, esp. when field is disrupted by solar flares. MHD. Ontario hydro lost a big 3 MVA transformer awhile back due to MHD during a solar flare.
 
Last edited:

mbrooke

Batteries Included
Location
United States
Occupation
Technician
Regarding the rest of your post, there's one significant difference between EMFs and mercury, asbestos, etc: Observable occupational health effects.

Asbestos: Health effects first noticed in 1899. First documented death in 1906. Massive number of worker deaths observed between 1900-1910. There were significant health concerns by the 1920-1930s. Your point that you'd be laughed at in the '60s is absurd. It was a known but accepted hazard.

Mercury: Health effects observed for centuries ("mad as a hatter") Medical reports published in 1823, possibly earlier. Significant study between 1923-1926. A known but accepted hazard.

Conversely, EMF has been studied upside-down and backwards for the better part of four decades, and there's still no proof of harm.

Regarding cellphones and cancer: If there was an effect, we'd expect to see a spike in brain tumors that coincides with the introduction of phones, and a marked decrease that coincides with the introduction of smart phones (a significant portion of use switched from beside the head to in front of the body) I've yet to see evidence of the first spike.

Yes, with the knowledge we have now. But at the time of the mad hatter, who actually knew it was Mercury? Before those medical studies, do you actually believe that not a single person had a suspicion and was never taken seriously because no medical evidence existed?

As for asbestos, if the health effects were known in the 1900s (and Im sure they were) and observable occupational health effects existed, then why was its use continued into the 70s? Why? Why is it that when I speak to everyone from the 60s and 70s they always say "we never knew it was dangerous"

Perhaps the evidence existed which has become well known now in 2014, but was such evidence known in the 50s? Even if it was known, how many people took it seriously?



We often don't question what is so common in our lives and work place because we always assume "its safe" and that just what asbestos workers in the 60s and 70s assumed.
 
Last edited:

mbrooke

Batteries Included
Location
United States
Occupation
Technician
however does a loop of copper in the earths field begin to generate voltage and current at the surface level

Yep, esp. when field is disrupted by solar flares. MHD. Ontario hydro lost a big 3 MVA transformer awhile back due to MHD during a solar flare.

Yes, but solar falirs are not a 24/7 365 day event? A running cell tower or transmission line is.
 

mbrooke

Batteries Included
Location
United States
Occupation
Technician
There are studies which show that some EMF sensitive people can defect very accurately whether the interviewer thinks the field is on. Not so much whether the field is actually on or off. So valid experiments need to be double blind by design.


IMO those studies whether people can feel EMF is BS. Just my opinion. I think whether or not someone can feel it is not a concern, if anything good for them. The issue at hand is what are the long term health effects for those who can not feel it which is the majority of people.
 
Status
Not open for further replies.
Top