High Voltage Overhead Power Lines - 12B Miltiadi Stilianou Street, Oroklini
The measurements were performed on the 14th of April 2011 at 10:00 am during clear weather conditions. The EMF measurements were performed inside the residence area and in direct proximity to the overhead power line. The following figures provide pictures of the area where EMF measurements were recorded.
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The overhead power line is rated at a nominal power of 280 MVA. At the time when the measurements were performed, the load of the overhead power line was 130 MVA. The Resultant Load of all three phases was 46 % utilisation of the nominal load power.
Limiting exposure values have been provided by the ICNIRP recommendations and are guidelines to many countries and organizations. The exposure limits at 50 Hz are tabulated in the following table according to the limits given by ICNIRP.
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Reference levels for Occupational exposure ICNIRP |
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Frequency |
Electric Field Strength, E (V/m) |
Magnetic Field Strength, H (A/m) |
Magnetic Flux Density, B (µT) |
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50 Hz |
10000 |
400 |
500 |
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Reference levels for General Public exposure ICNIRP |
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Frequency |
Electric Field Strength, E (V/m) |
Magnetic Field Strength, H (A/m) |
Magnetic Flux Density, B (µT) |
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50 Hz |
5000 |
80 |
100 |
Table 1: ICNIRP Exposure limits for Occupational and General Public exposure
The maximum electromagnetic field values obtained are represented below and compared to the ICNIRP specified limits of General Public standards. The highest magnetic field was observed below the overhead power lines, with a value 1.42 μT (12m away from the starting point when measuring the electric and magnetic fields along the overhead power lines) and a percentage of 1.42 % as compared to the ICNIRP General Public standard.
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Magnetic Field Measurements |
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Distance from Side /m |
Maximum Magnetic Field [μT] at Z Height /m - Percentage of ICNIRP General Public Standard /% |
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0.3m |
ICNIRP % |
1m |
ICNIRP % |
1.75m |
ICNIRP % |
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Measurements along the Overhead Power Line |
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30m measurement line |
1.03 |
1.03% |
1.23 |
1.23% |
1.42 |
1.42% |
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Measurements across the Overhead Power Line |
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30m measurement line |
0.90 |
0.90% |
1.05 |
1.05% |
1.20 |
1.20% |
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Measurements inside the residence |
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Measurement point A |
-- |
-- |
0.42 |
0.42% |
-- |
-- |
Table 2: Magnetic Field Measurements
Accordingly, the highest electric field was observed below the overhead power lines, with a value 316.48 V/m (0m away from the starting point when measuring the electric and magnetic fields across the overhead power lines) and a percentage of 6.33% as compared to the ICNIRP General Public standard.
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Electric Field Measurements |
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Distance from Side /m |
Maximum Electric Field [kV/m] at Z Height /m - Percentage of ICNIRP General Public Standard /% |
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0.3m |
ICNIRP % |
1m |
ICNIRP % |
1.75m |
ICNIRP % |
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Measurements along the Overhead Power Line |
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30m measurement line |
-- |
-- |
222.25 |
4.45% |
256.20 |
5.12% |
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Measurements across the Overhead Power Line |
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30m measurement line |
-- |
-- |
285.02 |
3.70% |
316.48 |
6.33% |
Table 3: Electric Field Measurements