We've wired a couple of homes now where the homeowners are wanting to reduce their EMF's. Generally we're running 14/3 everwhere, paying particluar attention to the bedrooms. Any experience or knowledge on how effective this actually is? Also, she is wanting to install some kind of device in or near the panel? where it will further reduce EMF's. HAven't seen this device yet or any of the specs on it.

EMF typically means Electro-Motive-Force...

But your client probably means Electro-Magnetic-Fields...

In which case, their alarmest demands would require some sort of shield and drain in the manner of FA cable or co-ax.

MI would do the trick. I hope they're billion-airs...


Alternately, you could construct their bedroom, etc. as a Faraday cage. Talk to the GC and the architect.

You could have them wear AFDBs

http://zapatopi.net/afdb/

HAHAHA... AFDB's.... ahhh that's good.

So... using 14/3 loomex as opposed to 14/2 loomex might not be reducing any further electro magnetic fields?

Tell them you twisted the Romex while you were running it to reduce the EMF. Those people who carefully unroll it so it lays flat are endangering your life.

It's a good idea to get MindGuard on your computer now so that its ready for when you really need it.

http://www.zapatopi.net/mindguard/

This is a link from electure's link, but he didn't point it out because he uses mac or windows and it's already too late...

Seriously, though, if that's possible, having all the conductors of a circuit in the same cable pretty much eliminates rfi interference. (That's what we're talking about, right?) To do more, bx is better. Try using a volt tick on bx. I've also noticed that dirty, wet loomex doesn't trigger a volt tick either. Maybe you can do something with that.

How does using 14/3 reduce the EMF?

Without being an expert with EMF, these are my thoughts and thoughts only. The metal casing of MC cables is about as good as EMT, which is I don't think either are to effective with EMF. If the conductors in the MC are rotating that will improve it over the EMT. The only conduit system shown to help with EMF is IMC or RSC, the only ones providing a thick enough sheild for 60 Hz.

With that said, EMF dissipates in a square of the distance, so another fix could be using recycled tires for walls stacking them horizontally and running the wire up through the center then bonding steel belts. This solution not only makes the home EMF friendly, it can be LEED certified for the reuse of materials and can qualify as the city dump.

On the other hand, in proper wired buildings, I have found almost no evidence of EMF in the wiring with the exception of panelboards and meters (due to separation of the conductors). So a solution for an EMF friendly home would be to intellegently place the load center(s) and meterbase in areas of infrequent traffic, then simply telling the owner to be careful of the devices used and installed (open motors, electric heating units, etc.). Overall, I don't worry about it other than to use EMF to track down problems in wiring.

Quote: Tell them you twisted the Romex while you were running it to reduce the EMF. Those people who carefully unroll it so it lays flat are endangering your life.

Greg, I actually had an Audio Engineer on a theater job that I did tell me to make sure that the 3-phase conductors were twisted around one another when they were pulled into the conduits "because twisting the wires reduces the noise".

To quote Bugs Bunny..."What a maroon".

How about this product? Made to replace Romex, it's not UL listed for use in walls.
http://www.lessemf.com/wiring.html
At $1.75 a foot.

It comes from this place:
http://www.lessemf.com/emf-shie.html

They list among their products shielded boxer shorts at $109.99, and a faraday cage that fits over a king-size bed for $999.00

They've also got a "High-Frequency ElectroMagnetic
Pollution Remover" that plugs into duplex receptacle, at 20 for $659.00!

I especially like their 3/8" Greenfield for $16.90 per foot. Now why didn't I think of this. Out come the tin foil hats!

How do you find this stuff?

Some grad students at MIT did a study with a couple different designs of the AFDB, and concluded it makes the "problem" worse by acting as an antenna and attenuating the signal.

I'll see if I can drum up the more "serious" site that sells underclothing with silver woven in with the thread, that's supposed to block harmful EMF.

Joetools,

As mentioned by the other Members, "Shielding" the Conductors is an effective method to reduce field emissions.

Shielding may be achieved by encasing Conductors in a Metallic Sheath, and by twisting the Conductors.

The Wiring methods performed on an installation, should have an overall result which balances the current flowing through any given Circuit, in a certain raceway or Cable.

This is stated as "Currents Canceling Each - Other's Fields".

A Two- Wire Circuit cancels the fields because each Conductor draws the same level of Current, but the Currents are flowing in opposite directions at any given point along the Two - Wire Circuit.

For example, a 120V 1200 Watt Heater connected with 12-2 NM Cable, will have 10 Amps flowing on the Black Conductor and the White Conductor.
Since these Currents are flowing in opposite directions at any given time, AND the Currents are of equal value on both Conductors, the Fields are canceled.

If the same Heater was connected to some other 2 wire Circuit's White Conductor, this would cause an imbalance of Current flowing in both of the affected 2 wire Cables, and thus would not cancel out the Fields completely.Let me know if you need more descriptions.

*** SIDE NOTE ***

If someone pulls out their "Field Sniffer" (milli gauss meter) to take field strength readings, be sure they know how to use it correctly!

Taking readings at very close proximity to ANY Discharge Lighting Devices (Fluorescent Lamps, HID Lamps, even CRT Televisions and possibly LEDs) will result in high level readings on ANY Meter!

Same will happen with Transformers and such.
The levels will rapidly drop as the distance increases.

Scott

Normal standard 12/2 romex is already EMF resistant, as the magnetic fields created by the two wires cancel out almost completely- the only reason it's not 100% is because the wires are separated by a few mm. You have to get right up on it to measure any field; at larger distances, they cancel pretty good.

If they're concerned about this, treat them like audiophiles and profit from their paranoia. A sealed metal raceway is an effective faraday cage. Wire the house entirely in compression-coupled EMT, and ensure every circuit is fitted with an EMF imbalance device (put a sticker on a GFCI). Make sure all the walls are covered with conductive foil. Caution them against using wifi or cell phones. Not that they'll will work with all the foil in their walls, but that's their choice.

If they're REALLY paranoid, you can built the entire home to HEMP standards, which not only protects them from nuclear EMP, but also from harmful emissions from their neighbor's wifi and their other neighbor's poorly sparking truck.

Steve;



Love the Audiophile reference!!!

Really love the paranoia references!!!

I forgot to mention to the OP, that type NM Cable will be fine for the installation - in either 2 or 3 Wire arrangements
with Conductors sized per application (i.e.:Circuit and Load sizes), of course!

The sad reality of your post is there are so many Clients, whom have been force-fed way too much Bandini-Tech regarding Electro-Magnetic fields, that the items in your Audiophile and paranoids lists would be taken as serious design parameters.

It is hard to explain to these Clients what is real, and what has been extremely fabricated.

Technically known as "Male Bovine Fecal Matter", most - if not all of the information regarding EM Fields, spewed out by Snake Oil Electrical Gurus, would be better used spread across Lawns; as it will make the Grass grow much greener!
(i.e.: Packaged in 2.0 cu. ft. bags, found in the Lawn & Garden Section of Home Centers, sold under the name of "Bandini")

Just look at the $150.00 Hubbell 5362 "Audio-Grade" Receptacle. That's one heck of a Bandini salesperson angle!

Thanks for mentioning the NM Cable, and especially for the humorous shielding options!

Scott

I suspect the root of all of this is the fear of powerlines. When someone pointed out the field from your house wiring is stronger than the field from that 100' tall power line they say "Oh no! my house wiring is going to kill me faster than that dangerous power line" and off you go.

You define a fear, real or imagined and someone will come along with a solution, real or imagined.

There is a guy who will take care of your pets after the rapture, for a small fee.

I don't care what you say. I recognize a good business when I see it and I already made my first sale! I calling in sick tomorrow, and then, well, we'll just have to see who laughs last.

Here's my first happy customer.



Is there a place on this site for advertising? EMF HATS FOR ALL!

Is anyone else amused that the truly paranoid people get completely bent out of shape about the powerlines running 20' overhead on poles in the alley, but don't make a peep about the same powerlines when they're run in the parkway 4' under the grass?

... or have an electric blanket.

Wow, this is a perfect example of the absolute worst-case scenario as far as household EMF goes. Unshielded, close to the body, and none of the fields cancel, just reinforce.

Joe, you need to go off on these people about how many people have died from cancer caused by electric blankets and how it's the leading cause of death, second only to food poisoning caused by agricultural insecticides. You know, something outlandish and tinfoily we'd all crack up laughing about, but say it with as straight of a face as possible and see if they call you on it.

If they don't... cha-ching! It's their money, give them whatever they want to pay for.

The problem with the AFDB is you look completely stupid in it and it could lead to fatal brain heat loss. My solution is to disguise the foil by incorporating it as the lining in a knitted wooly hat. Now, you can look like a total cretin, but with class!

Here, Mrs B and I model our Peruvian style. As you can see, the hats feature foil-lined flaps to keep the EMF from entering the brain via the earoles, and EMF deflector aerials on top. The chin-ties are handy if you need to go out under powerlines in a hurricane.

You're still getting EMF through your face!!! To be fully protected from mind-control rays, you need to use electrically conductive face-shields, grounded firmly about your neck. Better still, if it's 360 degrees around your entire body.

Australia

.(AP) A Sydney bomb squad evacuated neighbors and sent in robots to clear dozens of suspected explosives strewn about the house of a man who recently died, only to discover the devices were all fake, officials said Wednesday.

More than 50 bomb-like devices were found in the house and in the man's car, New South Wales state Detective Superintendent Gavin Dengate said.

The deceased man, a 69-year-old former electrician known as reclusive, apparently wanted to scare people away, Dengate said.

Friends of the man, whose identity was not released, called police after visiting his home Tuesday and spotting what looked like bombs. Neighbors were then evacuated as bomb squad officers sent in robots and detonated six of the devices, Dengate said.

"All of the devices were inert. ... They weren't capable of actually detonating," he said.

Some of the fake bombs were wired to appliances, and one included a pressure switch linked to two gas cylinders in a car.

The man, who died in a hospital more than a week ago, had also covered the windows in the house with aluminum foil.

Police have been unable to track down any of his family members.

"I have no doubt that he was not there to randomly injure people," Dengate said. "He was a recluse, and he wanted to remain that way."

Dengate said police did not know if the man suffered from a mental illness.

No, he was just shielding himself from the strong EMF fields because they drive everyone crazy

Steve, what like this?



[ Actually, truth to tell, this is Henry VIII's Field of the Cloth of Gold foot-armour from 1520 with its many overlapping parts - so remarkable that Nasa studied its construction when they were designing the first space suits in the 1960s. ]

Sorry, my mistake. This is from his 1520 collection. Flared skirts were in that year.

It is easy to laugh at the concept of an EMF friendly home, and to ascribe all interest in such to nut-jobs. Keep in mind, however that there is a certain amount of reality here, with some number of people demonstrably sensitive to stuff that you or I don't notice.

A very interesting set of anecdotes can be found if you search for posts by Karl Riley, both here and on the Mike Holt board.

1) We say 'EMF', but since we are dealing with the 60Hz wiring surrounding us in homes, we really should not think in terms of electro-magnetic radiation (energy radiating through space, where energy is constantly flowing between a changing electric field and a changing magnetic field), but rather we should be thinking in terms of near field approximations, where currents in wires are creating magnetic fields, or charged wires are creating electric fields.

2) What I take from Karl's anecdotes is that the vast bulk of situations where people could 'sense' or be adversely affected by wiring could be ascribed to _magnetic_ fields. These magnetic fields are caused by unbalanced current flows, meaning current flowing in a conductor that is not matched by current flowing in the opposite direction in an immediately adjacent conductor. The vast bulk of these situations are actual code violations, eg. bootleg neutrals, unintentional parallel neutrals, etc. In other words, the bulk of the situations where people 'feel' the wiring were situations where there is a well defined code violation that can be fixed. What this means is that careful adherence to code will get you most (if not all) the way to an EMF friendly home.

3) Code does permit some situations that can cause significant unbalanced current flow; eliminating this becomes a design issue. The big one that I can think of is shared underground metallic water piping acting as a parallel neutral. For an 'EMF friendly' home, I would suggest plastic underground piping to eliminate this shared neutral path.

4) In the US, conventional 120V wiring has one 'hot' and one 'grounded' conductor; this will produce a net _electric_ field between the cable and the surroundings. If someone is sensitive to electric fields (as opposed to magnetic fields), then running a MWBC with both supply legs present in the same cable would seem to reduce this. Using wiring methods surrounded by grounded metal would also likely reduce this. (Again note: we are talking about electric and magnetic fields separately here, and it seems that people are sensitive to _magnetic_ fields if anything.)

5) My personal _hunch_ is that the low intensity electric and magnetic fields produced by home wiring do no direct health damage, but that some people are just sensitive enough to them to be annoyed by them, without being able to clearly identify the problem and so be able to decide to ignore it. This continual annoyance is what then triggers health damage. I personally experience this sort of thing where an extremely quiet but unidentified sound will keep me awake, while I try to figure out what the hell is making the noise and wishing it would go away. Most people would just sleep through the sound, but it grabs my attention, sets my teeth on edge, and ruins me the next day. Perhaps these people are particularly sensitive to audible 60 Hz hum, and the magnetic fields make things vibrate, and the vibrations are what annoy them. Perhaps these people really do barely detect the changing magnetic field itself. I don't know.

6) There are lots of BS artists out there selling things related to EMF.

-Jon

I saw that in the Tower of London exhibit a few months ago; it's an amazing piece of protective technology. Incredible that even in the 1500s, they knew of the dangers of even just natural EMF and took moves to protect themselves from it.

It's official. Scientists now think an AFDB is an essential accessory for the modern man-about-town to protect his brain from stray EMF, fridge-magnets etc., causing an inexhaustible appetite for donuts.

http://blogs.telegraph.co.uk/news/georgepitcher/100032134/official-diy-is-immoral-or-something/