|
Post Time: 01/04/2008 17:52:55 |
nickmarshall
Total Forum Posts: 2 |
We've found our 'ideal' home we're hoping to buy, but have discovered there is a small electrical substation behind the fence to the side of the house, which itself is fenced in only, with an open top.
I've hired a EMF reader and the readings are around 4.0 next to the fence, and drop off to around 0.3 at the corner of the house which is the closest to the fence, only 2m away. Any further away, outside the house, and the levels drop to 0.1 to 0.2.
We have a 2 year old daughter and we're very concerned about the information we read about the health effects of EMFs. However, she will be sleeping at the other side of the house, and from what I can see the substation appears to be only small.
I've asked the surveyor to take internal readings this week, and are waiting for his reply.
Does anyone have any advice on what we should do - is it safe to live next door to one of these small substations? What kind of levels should we be looking for inside the house?
Does anyone have any thoughts to how the resale value of the house might be affected by having this small substation next door?
Thank you for your advice.
|
|
Post Time: 02/04/2008 09:13:12 |
Sarahp
Total Forum Posts: 48 |
Hi Nick
Rather than me typing out a huge long post in reply, can I refer you to two subscriber articles that seem to be directly relevant, and will probably answer your question in far more detail than a few paragraphs here.
I refer to "Buying an EMF safe Property" (third publication from the top) and "Powerlines and Substations" (in the section Articles: Substations, Powerlines and Related EMFs, which is close to the bottom of the page).
The first one is 40 pages, the second 7 pages. If, after reading those two, you still have specific questions, please feel free to post again :)
Sarah |
|
Post Time: 04/04/2008 18:23:54 |
alasdairP
Total Forum Posts: 173 |
The level at which a doubling in incidence in childhood leukaemia has been repeatedly identified is between 0.3 and 0.4 microtesla. I recommend levels inside a house should not exceed about 0.25uT, and not above 0.1uT in bedrooms. The levels are likely to be higher in winter than in summer. Also bear in mind that a house with a substation next to it will be slightly harder to sell when you want to move and are already usually slightly discounted in value, from a few percent to maybe 15% for a large very obvious one close to the house. In your case I would suspect only a few %, but it is difficult to say what will occur in the future. The issue will not go away and the 0.3 to 0.4 uT level is pretty well agreed internationally now. The presence of the substation will undoubtedly make the house slightly harder to sell.
Alasdair
|
|
Post Time: 06/04/2008 18:32:16 |
nickmarshall
Total Forum Posts: 2 |
Thank you for the information...
With the current owners' permission we have re-checked the levels and have confirmed the following:
0.5m from the fence we have recorded 1uT
2m from the fence we record around 0.2uT
We have also now discovered a pattern of what is probably a underground power line leading from the substation across the width of the garden. At absolute ground level, we have recorded 0.7uT within a metre either side, which drops off to 0.2uT quickly aside from that. Around 0.2uT is found around most of the rest of the garden.
Inside the house, most of the downstairs rooms fall within 0.2uT, and the upstairs bedrooms are below 0.1uT, which gives us some assurance.
We are concerned at the levels we are seeing in the garden, however. We had previously considered screening the fencing in front of the small substation - we contacted a company we do this kind of thing for businesses, and they kindly provided us with basic information on how to create an effective large scale screen using 3-ply sheet steel, which would needed to be welded at all joins to create a 'water-tight' barrier. This could then be visually screened by normal fencing. We acknowldge the cost would be consideredable, but could be kept lower by finding a local metal working company to carry out the job, and considering the cost of the house, would be be nominal.
However, now we have the problem of what appears to be an underground cable creating a band of elevated readings across the garden.
Does anyone know if there is a feasible way to screen underground cables? Indeed, does anyone have any exerience of screening low frequency EMFs?
It seems electo-magnetic levels inside the house appear to be within safe limits, however, outside is where the problem lies. We've read with interest, Alasdair, about the levels at which childhood leukemia can be doubled, but we're unsure how to measure this... Do we base this on an average exposure, or highest exposure? If our daughter sleeps in less the 0.1uT, and lives mostly in less than 0.2uT, but during the summer months plays in the garden with the kind of levels I mention, does this put her at risk? What are the risks in real terms? How many cases of childhood leukaemia have been recorded in the UK, and how do they relate to the kind of levels we have identified?
Genuine thanks for any help in gathering the information we need.
|
|
Post Time: 10/04/2008 17:47:25 |
alasdairP
Total Forum Posts: 173 |
Sorry about the delay in responding.
1/. The levels you mention are generally OK and seem OK in the house, though they are higher than the UK average which we, and the electricity industry, agree is in the order of 0.04 to 0.05 microtesla 50 Hz magnetic fields. The official industry EMF site is now really very good.
See: www.emfs.info/default.asp
2/. If the cable crosses the garden then this should be recorded in the Deeds of the house. It will either be a wayleave (a renewable lease to use the land) or a permanent easement (they buy the rights to have the cables there with a smallish one-off payment). Sometimes cables run across and under land without permission - this is more common than you might think, for a variety of historical reasons. You can then give them "notice to quit" and move their cables from your property. They sometimes then ask for a wayleave hearing (in front of an engineering inspector) and say it is necessary to keep the cables there, but that is unlikely just for a short length of underground cable across you garden - it would be cheaper and easier to move the cable.
3/. In my professional experience it is VERY difficult to shield out mains frequency magnetic fields other than by re-designing the substation and/or putting a complete shielded box around the substation transformer and moving the cables further way from where you want low fields. The cables can be run in a steel pipe and/or a fabricated steel box (at least 6mm steel is needed) but the network companies will not normally agree to this.
The readings you state should be OK as regards not having any ill-health effects, but the property will be harder to re-sell located next to a substation, even a small one. Also, the fields are higher than the UK averages (about 0.2 uT for detached houses set back from a road to about 0.08 uT for normal semis close to the pavement with small front-gardens). So, as long as you are not planning to move for a reasonable length of time, then it should be OK. If the house is ideal for other reasons, then the substation is not a great problem. You will have to make the value judgement on that - there is no absolute answer. The discounting probably varies from about 5 to 15% on the value of the property without the substation next door. If you were not in a hurry to sell, then a 5% figure might be reasonable. That is from general discussions with estate agents and others over recent years. Sally Sims at Oxford Brookes University did some work on effects on house value, but that was now some years ago and was more concerned with overhead powerlines. There is some discussion of the isses re powerlines in SAGE supporting document S17 which can be downloaded from the Dept Health website. There is a download link at the bottom of this Powerwatch page:
www.powerwatch.org.uk/news/20070429_sage_comments.asp
I hope that helps. |
