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EMF ASSESSMENT BY MEASUREMENT (IVORIAN CASE ). GUY-MICHEL KOUAKOU Head of standardization service VICE-CHAIR OF STUDY GROUP 5. PLAN. National Context . EMF assessment. Flowchart for measurement. Measuring equipment . Post-processing analysis. Some statistics. Conclusion.
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EMF ASSESSMENT BY MEASUREMENT (IVORIAN CASE ) GUY-MICHEL KOUAKOU Head of standardization service VICE-CHAIR OF STUDY GROUP 5
PLAN • National Context • EMF assessment • Flowchart for measurement • Measuring equipment • Post-processing analysis • Some statistics • Conclusion
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)
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
Résultats> limites CIPRNI Exigences de protection de la santé respectée Exigences de protection non respectée FLOW CHART
ANTENNESA EME SPY 120 (88Mhz - 3Ghz) Switch Tri axis Probe Spectrum analyser Anritsu MS2721B EMF from différent services (TV, FM, GSM …) z x y z x y MEASURING EQUIPMENT • For case 1: RF radiation meters with isotropic field probes and a dosimeter EMR 300 W/G (10 Khz - 3 Ghz) • Cases 2 & 3: Spectrum Analyser
POST-PROCESSING (1/2) • Measurement uncertainty estimation according to IEC guide: • For each case equipment uncertainty was taken into account. IEC “Guide to the expression of uncertainty in measurement Ed. 1, 1995
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 Channelx sqrt (n Transmitteers) • The determination of « n » was done in accordance with typical base stations configurations. • For each location an extrapolation factor was estimated.
RESULT Every measurement was found to have been in compliance with ICNIRP limits.
Average field level per service Ratio between average value and ICNIRP limits SOME STATISTICS • The average field level per service 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 • According to ICNIRP limits. GSM 900 represent 3.31% and GSM 1800 represent 4.70%
Field level distribution per service SOME STATISTICS • For GSM 900 : 98 % of field levels was less than 10% of limits value (4 V/m) ; • For GSM 1800 : 89 % of EM field was less than 10% of limits value (5.68 V/m);
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 multi-operators environment.