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Living under/near the transmission line (150 kV line)

Living under/near the transmission line (150 kV line)

Living under/near the transmission line (150 kV line)

(OP)
Dear friends, I've some questions here.
1. If we live under/near 150 kV transmission line, will it give us negative effect for our health?
2. How much the safe value of Electric Fields and Magnetic Fields  so that they would not give us negative effect
3. How far is the safe distance (minimum distance) from our house to the 150 kV transmission line so that the 150 kV line would not give negative effect to our health?
Thanks for your attention  

RE: Living under/near the transmission line (150 kV line)

There are no negative effects from electric fields or magnetic fields.

There may be negative effects from heavy metal oxides and salts falling from overhead conductors and poles, but that is only if you grow vegetables or eat the grass (as cows and other animals do) under the power lines. This is a suspicion and not an established truth.

The distance where 150 kV gets dangerous is when you get so near that the voltage flashes over and hits you. But you do not do that, do you?

The worst influence on your health is that you worry about this harmless thing. Don't worry - be happy!

 

Gunnar Englund
www.gke.org
--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.

RE: Living under/near the transmission line (150 kV line)

Here is a link for additional info:

http://www.emfs.info/Related+Issues/limits/USA/

The US has no specific limits although some individual states and other countries have set limits.  This was studied ad infinitum in the 1980s and 1990s.  As Gunnar already stated, there is no evidence that the low frequency electric and magnetic fields associated with overhead power lines create any health hazards.  

 

David Castor
www.cvoes.com

RE: Living under/near the transmission line (150 kV line)

Powering2002,
although an  relationship between power lines and cancer has not been demonstrated there are some concerns and correlation studies have been extensively carried out. In Europe national limits for magnetic field exposure vary between 10 and 0.2 uT. The latter should mean a "safe" distance of about 30-40 meters for a 1000 A /150 kV power line.
 

RE: Living under/near the transmission line (150 kV line)

Gunnar,

Is that why the grass I eat when I'm under the power lines tastes mysteriously like a good single-malt scotch whiskey?

Good on ya,

Goober Dave

RE: Living under/near the transmission line (150 kV line)

I live with the 0.2 uT limit.

Swedish authorities say that "continuous children activities in areas with more than 0.2 uT shall be avoided".

The US limits, that are 100 times higher, may have some justification but no research has been able to prove any correlation between magnetic fields and cancer.

There was an epidemilogical study some twenty or thirty years ago where there seemed to be a correlation between leukemia in children and location - and then someone drew the conclusion that there was a correlation between location and magnetic field strength - totally unfounded. Just based on differences in electrical wiring practices - no measurements were made.

How did the 0.2 uT limit come about then? I guess someone asked a physics professor, and he didn't know what to answer. So, he plugged all ones into the Biot-Savart formula and out came 0.2 uT.

That is how the world is run these days.

Gunnar Englund
www.gke.org
--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.

RE: Living under/near the transmission line (150 kV line)

"There are no negative effects from electric fields or magnetic fields"

Really?

Do you know how people get Cancer? Even the top notch doctors can not tell how the cancer cell was created.

There are things that we don't know based on present technology but it does not mean it has no negative impacts. I am an electrical engineer I will never buy a house close to any transmisison level towers.

RE: Living under/near the transmission line (150 kV line)

As far as i now all the study were focused on finding a correlation between magnetic field exposure and disease incidence, but none has evidenced a cause / effect  relation.  IMHO someone took the statistical data of population living near HV/EHV power lines (that means in most of cases in industrial areas or in big cities, thus inherently including hundreds of other risk factors ); nor physics neither medical theories, just statistics. Of course, being this issue yet not completely clear the general apporach is "the farest the better".
0.2 uT is the same order of magnitude of the magnetic fields generated by low voltages appliances and maybe it could have been considered as the base exposure level of the whole population...    

Si duri puer ingeni videtur,
preconem facias vel architectum.

RE: Living under/near the transmission line (150 kV line)

QBPlanner,

If you are making the claim that the exposure causes cancer it is up to you to offer the evidence to support this claim.  Despite numerous studies and millions of dollars spent, there is not any substantiated correlation between cancer and EMF exposure, much less any proof of causation.

It is not possible to prove a negative.  





 

David Castor
www.cvoes.com

RE: Living under/near the transmission line (150 kV line)

Quote:

Do you know how people get Cancer? Even the top notch doctors can not tell how the cancer cell was created.
That's why I'll never buy a house next to a [school][dairy farm][Wal-Mart][forest][anything else you can think of, take your pick].  There are no studies showing conclusively that these things don't cause cancer.
soapbox

RE: Living under/near the transmission line (150 kV line)

A disproportionate number of workers from the heavy oil upgrading plants die prematurely from cancer. The incidence of cancer among workers in some areas is very high. Many of these fellows only see a few years of retirement. As with smoking and lung cancer, second hand smoke and cancer and global warming there is no proven link.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Living under/near the transmission line (150 kV line)

(OP)
FPElec,
So, it is safe for us to live in a house located 125 meters from 150 kV Transmission Line. Isn't it?

RE: Living under/near the transmission line (150 kV line)

Powering2002,
I think that such a distance is considered safe by any national regulation. The EMF fields generated from a 150 kV line at more than 100 m far are not higher respect to most electrical appliances.
BTW my working desk is less than 10 meters far from a 150 kV line ...

Si duri puer ingeni videtur,
preconem facias vel architectum.

RE: Living under/near the transmission line (150 kV line)

It is not easy to say if your place is safe or not.

There may be earth-quakes, tornados, flooding, wild animals, nearby dumps, wildfires and many other dangers. It is really hard to say anything about the risks where you live. A derailed train can hit your house if you are close to a railway.

But, the 150 kV transmission line is not a risk. Just make sure the insulators don't break while you are right under the line - that will not be good for you.

Gunnar Englund
www.gke.org
--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.

RE: Living under/near the transmission line (150 kV line)

To DPC:
It is not up to me to prove anything. Before 1970s Mohave broke their generator shafts, nobody knew about what Torsional stress was.

Read my post carefully, Did I make any claim? I just simply stated the facts there are many things that we could not explain but it does not mean they do not exist. Being an electrical engineer for many years with some limited knowledge on power system. I don't claim I know everything. Due to some reasons, I talked to some top notch doctors mainly focused on Cancer research. They told me they could not tell how the cancer cell came from.

jghrist :
You can go ahead buy your house anywhere you want and I don't really mind. It is your choice and nobody force you to stay close to the transmission lines.

Being professional is good thing but being ignorance is something difference.
 

RE: Living under/near the transmission line (150 kV line)

The science/math shows that there is likely minimal exposure (if any) due to the transmission line and reasonable distances.  Certainly not a significant increase over background EMF and much lower than one would see with a radio transmitter on their hip (cell phone).  

With that said, however, I would still try to place my house on a plot of land so it was no closer to the HV line than necessary.  Or, if I were buying a lot/house with a HV line near it, that would certainly factor into the price in my mind, as I know that others will give it less value in the future in spite of the scientific evidence.

I guess I would look at it from an economic point of view.  If I were receiving adequate compensation to account for any diminshed resale value due to the HV line, I would have no qualms locating near one.  From a practical standpoint I would stay as far away from it as is reasonable to avoid conflicts and other issues (such as having a bucket truck in my front yard some day for repairs :)  ).  I wouldn't worry about safety as far as living in the house unless it was directly below the lines, and I suspect the utility won't let you build there anyway... :)

RE: Living under/near the transmission line (150 kV line)

Sorry Dave, I didn't notice your question about whisky-tasting grass.

Although I regard myself as a professional whisky drinker, which is good (se QB 27 Sep 11 12:02), I must confess that I am ignorant (which is different (se QB again) and I have no explanation for what you have experienced.

It is an interesting find, however. And much more plausible than any claim about getting cancer from VLF magnetic fields. I can think of the following chain of causes:

1. The poles are made from oak.
2. Poles have been charred to better resist rot. That is better than using arsenik, which is known to be bad for living creatures and should be avoided.
3. As you know, whisky is stored in charred oak barrels to mature.

Conclusions follow more or less automatically, but be aware that more reaserch is needed.

Gunnar Englund
www.gke.org
--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.

RE: Living under/near the transmission line (150 kV line)

Have you guys ever been to the wind farms.I have been to two wind farms. I found out that the grass within the wind farms were shorter than the grass outside. I could not tell the reasons from electrical aspects or maybe the wind farms I have been to are special cases because the soil under that two wind farms are just not as good as the these of the other parts.They are in different locations. people always say wind farms is the most clean energy in the world now. I can not comment it.
In this world, everybody is different. Some are very healthy some are not. I recalled when I was searching the house years ago, there is one cute house with very nice layout and a small backyeard then I saw 2 60kV steel tower approximately 30 meters away from the house. Right away I knew the house is adjacent to the line R/W. I stood there for 5 minutes I can hear the small noise from the line.
Back to about 5 to 6 years ago, in Canada BC, people in a small town strongly opposited the new 230kV line running through their back yard. Regardless of what BC Hydro show the EMF study results based on either the link posted by DPC ot some other study results, BC Hydro were forced to buy out these houses. there were approximate 50 houses were old to BC Hydro. I would suggest you to find out how many houses BC Hydro sold out up to today.
Of course, you can still make jokes about these 50 home onwers such as " next to a [school][dairy farm][Wal-Mart][forest][anything else you can think of, take your pick]."
 

RE: Living under/near the transmission line (150 kV line)

More research, of course.

QB, that people react in funny ways is not new. And that they are greedy isn't news either.

Gunnar Englund
www.gke.org
--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.

RE: Living under/near the transmission line (150 kV line)

One more story happened to the people I knew. A gilr worked in a HVDC station (Old type mercury arc )she had twice mis carrage.

Finally she started to doubt about the working places and requested to be transferred to office work. Maybe two years (I don;'t remember exact one or two years) later she got a baby. You can dispute that she was not very healthy during the twice mis carrage time ot it is her own fault and get nothing to do with the HVDC station. I would say it could be. Who knows?  

RE: Living under/near the transmission line (150 kV line)

Mercury rectifier. Doesn't that say it all?

Those older rectifiers were not hermetically sealed but had ion pumps to keep vacuum. Any idea where the fumes went?

Gunnar Englund
www.gke.org
--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.

RE: Living under/near the transmission line (150 kV line)

QB,

The fact that BC Hydro bought some houses doesn't prove anything regarding EMF hazards.  

This anecdotal "evidence" is not meaningful data.  Some people get sick and die, others live to be 100.  Humans are hard-wired to look for patterns and correlations.  That helped keep our ancestors alive.  But a lot of these correlations are meaningless.  

 

David Castor
www.cvoes.com

RE: Living under/near the transmission line (150 kV line)

To Skogsgurra:

No problems of being funny or even greedy. It is a free world. Take your pick QB is a stupid or a stubborn guy. No problems.

I just offered my two cents here and some real cases that I have no answers. I wish I should have done another Ph.D on the potential impacst between cancer and power system EMF. However, that will require me to start in a Medical school first.

 

RE: Living under/near the transmission line (150 kV line)

Perhaps I wasn't clear enough. Mercury rectifiers work with a pool of mercury and a rarefied atmosphere in which the arcs burn.

Mercury (Hg) is very bad to animals and especially bad for reproduction organs.

I didn't mean to say you were either stupid or stubborn. All I wanted to point out is that if a young female person works in a mercury polluted environment, the first thing to suspect isn't the electric or magnetic field for which no correlation with reproduction deficiencies is known.

Isn't the proven bad effect on reproduction a much more plausible explanation?

Gunnar Englund
www.gke.org
--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.

RE: Living under/near the transmission line (150 kV line)

Hi Gunnar Englund
Thanks for telling me that "Mercury (Hg) is very bad to animals and especially bad for reproduction organs."

Hi David:
NC Hydro can not prove anyting either. In a word some people believe something and other don't

RE: Living under/near the transmission line (150 kV line)

just make sure your house is outside of the fall zone of the transmission line/pole/tower. . .

that is the only factual answer as to the risk of living near such rights of ways!

RE: Living under/near the transmission line (150 kV line)

Quote:

I found out that the grass within the wind farms were shorter than the grass outside. I could not tell the reasons from electrical aspects or maybe the wind farms I have been to are special cases because the soil under that two wind farms are just not as good as the these of the other parts.They are in different locations. people always say wind farms is the most clean energy in the world now.
More Occam's razor type discourse here. I too have been to MANY wind farms, and your observation is not without basis. But I came to a totally different, and in my opinion, more plausible explanation. Raptors, a major natural check and balance to rodent overpopulation, get killed in very high numbers by rotating windmill blades, especially the 3 blade smaller varieties. With fewer surviving raptors, the rodents eat more of the grasses, not just the seeds, as their population explodes rapidly.  My conclusion was formed by seeing countless little field mice and prairie dogs scurrying around everywhere I walked. If EM fields were affecting the grass length, shouldn't it have been affecting the rodents too? If not first? Same base observation, different conclusion based on evidence at hand, not pre-conceived ideas. Like the mercury rectifiers, a much more likely explanation.

I might be mistaken, but in one of the previous discussions I've been involved in on this very subject, someone had pointed to an epidemiological study on electric power line workers, a group that is disproportionately more exposed to HT lines and their magnetic fields, and there was no conclusive evidence of any increase rates of anything, including cancer. I'll see if I can find it.
 

"Dear future generations: Please accept our apologies. We were rolling drunk on petroleum."
— Kilgore Trout (via Kurt Vonnegut)
  
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RE: Living under/near the transmission line (150 kV line)

RE:  Mercury AND magnetic fields.

With a previous employer, we had a DeNora process  (mercury cell) chlor-alkali unit.  It used mercury, nice, shiny, elemental mercury by the ton, with the inevitable leaks.  The input current for the cell line was 300 kA at 350 VDC.  the magnetic field was strong enough to pull ferrous hand tools into the bus from six feet away.

We could find no 'off the shelf' technology to measure magnetic fields of this magnitude.

I worked there ten years.  I'm perfectly normal except for the tendency to emit a soft bluish glow in the presence of electricity.

old field guy

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