EMF ASSESSMENT BY MEASUREMENT
(IVORIAN CASE )
GUY-MICHEL KOUAKOU
Head of standardization service
VICE-CHAIR OF STUDY GROUP 5
1
PLAN
• National Context
• EMF assessment
• Flowchart for measurement
• Measuring equipment
• Post-processing analysis
• Some statistics
• Conclusion
2
NATIONAL CONTEXT
• Major public concerns, misinformation about EMF health related issues and
particularly EMF effects from base stations.
• Many people are against the installation and deployment of base stations in
their neighbourhoods.
• No legal protection framework in place for EMF related health issues.
• ATCI (National Regulatory Authority) ensures the need to protect human
health by adopting international standards such as:
– ITU-T recommendations for compliance and estimation of EMF (K.52,
K.70)
– ICNIRP (International Commission on Non-Ionizing Radiation Protection)
recommendation for exposure limits
– CEPT recommendation for measurement procedures (ECC(02) 04
revised)
3
EMF ASSESSMENT
• Measurements campaign in the town of Abidjan (the capital).
• Measurements were carried out in the 10 KHz to 6 GHz band
• First step: 103 locations were identified for measurements but later
restricted to 43 locations using a decision level of 0.3 v/m.
• EMF Estimation for these locations were carried out using the EMF estimator
(K.70) and technical characteristics of base stations at the varoius points.
• In situ measurement: about 3 hours per location (1 month for all locations)
• some words about measurement protocol
– Based on three cases;
– Case 1 for quick overview to find the point where the field is higher (1.1, 1.5,
1.7)
– Cases 2 & 3 for detailed investigation which allow to scan variable frequency
band to deal with specific services
4
FLOW CHART
Exigences de protection de la santé
respectée
Résultats>
limites CIPRNI
Exigences de protection non
respectée
5
MEASURING EQUIPMENT
• For case 1: RF radiation meters with isotropic field probes and a dosimeter
EMR 300 W/G (10 Khz - 3 Ghz)
ANTENNESA EME SPY 120 (88Mhz - 3Ghz)
• Cases 2 & 3: Spectrum Analyser
EMF from différent
services
(TV, FM, GSM z…)
Switch
Tri axis Probe
Spectrum
analyser
Anritsu
MS2721B
x
x
y
z
y
6
POST-PROCESSING (1/2)
• Measurement uncertainty estimation according to IEC guide:
• For each case equipment uncertainty was taken into account.
CAS 2
Uncertainty of xi
Input quantity
Value
(dB)
Antenna Factor
2,00
Cable
0,20
isotropy
1,70
Receiver
2,00
distribution
U(Xi)(
%)
Ci
(CiU(Xi))2(%)
normal
25,89
1,00
12,95
2,33
1,00
1,16
21,62
1,00
12,48
25,89
1,00
12,95
rectangular
Combined standard
uncertainty (66% )
21,29
Expanded uncertainty
(95 %)
41,74
IEC “Guide to the expression of uncertainty in measurement Ed. 1, 1995
7
POST-PROCESSING (2/2)
• GSM measurement extrapolation was considered for maximum possible
traffic. Measurements were done only for the permanent control channel.
The extrapolation to the maximum traffic is then calculated by the following formula
Emax = E Control Channel x sqrt (n Transmitteers)
• The determination of « n » was done in accordance with typical base
stations configurations.
• For each location an extrapolation factor was estimated.
8
RESULT
Every measurement was found to have been in
compliance with ICNIRP limits.
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SOME STATISTICS
• The average field level per service
E(V/m)
2,669
3
3
2
1,336
2
0,720
1
0,312
0,378
0,042
0,044
0,023
0,033
Exploration
RADARS-BLR-FH
DECT
GSM 1800
RADARS -DAB
GSM 900
TV
PMR-BALISE
FM
PMR
HF
0
0,241
0,015
1
was low (under 1V/m) except for
GSM service where the average
levels were 1.336 V/m for GSM
900 and 2.67 V/m for GSM 1800
Average field level per service
• According to ICNIRP limits.
E(V/m)
10%
GSM 900 represent 3.31% and
GSM 1800 represent 4.70%
8%
4,70%
6%
3,31%
2,57%
4%
0,86%
2%
1,12%
0,12%
0,62%
0,07% 0,07%
0,05%
Exploration
RADARS-BLR-FH
DECT
GSM 1800
RADARS -DAB
GSM 900
TV
PMR-BALISE
FM
PMR
HF
0%
0,05%
Ratio between average value and ICNIRP limits
10
SOME STATISTICS
Exploration
satellite,
RADARS-BLRFH
DECT
GSM 1800
RADARS -DAB
GSM 900
TV Bande IV et V
1%< niveau < 2%
PMR-BALISE
2%< niveau < 5%
• For GSM 1800 : 89 % of EM field
Radio FM
5%< niveau < 10%
was less than 10% of limits value
(4 V/m) ;
PMR
10%< niveau < 100%
• For GSM 900 : 98 % of field levels
service HF
100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%
was less than 10% of limits value
(5.68 V/m);
< 1% de la valeur limite
Field level distribution per service
11
CONCLUSION
• ATCI will work with GSM operators to reduce the level of exposure accordind
to mitigation technics proposed by recommendation UIT-T K.7O.
• ATCI will use EMF estimator to assess the compliance of base station before
their installation.
• K.GUIDE should include :
– A detailed measurement procedure taking into account the work done by CEPT,
CENELEC and IEC.
– A procedure to choose relevants location for measurement
– A methode to caculate extrapolation factor for GSM in multi-source and multioperators environment.
12
THANK YOU FOR YOUR
ATTENTION
?
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