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"This should have been rewired in 1960".
For reasons other than just "it's old", I hope?

"Therefore, the safety concerns are not about the knob and tube wiring itself but the
alterations and modifications performed on the original wiring."

Also see pg 16 of
http://www.pct.edu/nssc/docs/articles/KnobTube_Report_WTC.pdf

A cable maker told me that Romex has a life of 50 years but at the same time was unable to define "End Of Life."

It seems politicians, and others, hate dictionaries.
 

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Electrical Contractor
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What many people don't know about K&T is that it is not compliant to be installed in insulation. Tell that to the insulation guys who have covered millions of K&T homes with their product.

K&T also creates unwanted electromagnetic field's in the home. Some people have claimed they get tense and have a hard time functioning in those homes.

This phenomena is becoming more and more coming. I am getting about a call a month because of electromagnetic field's. I have gotten calls from NJ and TX as well. I guess the forum has advertised my knowledge of the electromagnetic field's from other forums where I moderate. That is how they found me--lol
 

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What many people don't know about K&T is that it is not compliant to be installed in insulation. Tell that to the insulation guys who have covered millions of K&T homes with their product.

K&T also creates unwanted electromagnetic field's in the home. Some people have claimed they get tense and have a hard time functioning in those homes.

This phenomena is becoming more and more coming. I am getting about a call a month because of electromagnetic field's. I have gotten calls from NJ and TX as well. I guess the forum has advertised my knowledge of the electromagnetic field's from other forums where I moderate. That is how they found me--lol
K&T makes people tense because they fear their house will burn to the ground any second. Nothing to do with electromagnetic fields.
 
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Some people have claimed they get tense and have a hard time functioning in those homes.
The EM field around Romex is less than K & T because the conductors are closer together. It would be even less if the Romex were laid on a conducting surface.

A wavelength at 60 Hz is thousands of miles and the length of a human body is a very small fraction of this and so it picks up very little of the transmitted field.
They may believe, however, that it's the EM field.

Duke has/had a PSI lab and they may have tested people for EM sensitivity.

More plausible IMO is ions in the air, for whatever reason.
 

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Electrical Contractor
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The EM field around Romex is less than K & T because the conductors are closer together. It would be even less if the Romex were laid on a conducting surface.
Correct-- nm is not an issue with electromagnetic field's but K&T is very much a problem. MC cable or conduit, of course is the best way to shield it but not often done.

Now depending on how you wire the circuit nm cable can be a problem also. I have repaired many issues with nm that was causing electromagnetic field's
 

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Electrical Contractor
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I thought low freq. magnetic fields (H fields) are hard to shield. What issues and how did you do it?
I am not really shielding them but eliminating them. Here are 3 very common problems I find where nm cable causes electromagnetic field's.

1. If the EGC is touching the grounded conductor after the OCPD.
2. If the grounded conductor from two different circuits are connected together after the Ocpd. I see this in 2 or 3 gang switches where either the neutrals get crossed or they are all tied together.
3. If the circuit conductor are not run together as in K&T wiring or sometimes you see this in 3 way switches where the EC runs 2 wire cable between the 3 ways and picks up a neutral at one box and the feed at the other.
 
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