Workshop "Acute Health Impairment", Dec 12-13, 2006 Exposure of the general public to RF electromagnetic fields Dr. Christian Bornkessel, IMST GmbH, Carl-Friedrich-Gauss-St. 2, D-47475 Kamp-Lintfort [email protected] IMST GmbH Carl-Friedrich-Gauß-Strasse 2 Tel.: +49-2842-981-0 47475 Kamp-Lintfort Fax: +49-2842-981-199 www.imst.de E-Mail: [email protected] Outline • RF sources and their exposure - relevant exposures in everyday life - focus on general public exposure - exposure results with special regard to DMF studies • Personal exposure meters (Dosimeter) - available dosimeters - typical results Folie 2 Exposure of general public, November 07 Classification of relevant RF sources Installation type Fixed Mobile Mobile phone Mobile phones base stations TV broadcast DECT phones transmitters Radio broadcast WLAN applications transmitters Folie 3 Exposure of general public, November 07 Classification of relevant RF sources Installation place Outdoor Household Mobile phone Mobile phones base stations TV broadcast DECT phones transmitters Radio broadcast WLAN applications transmitters Folie 4 Exposure of general public, November 07 Classification of relevant RF sources Distance Close to body Far field or body contact Mobile phone Mobile phones base stations TV broadcast DECT phones transmitters Radio broadcast WLAN applications transmitters Folie 5 Exposure of general public, November 07 Mobile phone base stations Frequency: - 925 – 960 MHz (GSM 900) - 1820 – 1880 MHz (GSM 1800) - 2110 – 2170 MHz (UMTS) Transmit - typ. 5-30 W/channel/sector Power: - 100-1800 W (EIRP)/channel/sector Transmitter:- ~85,000 stations in Germany Coverage: - 500 m – 20 km Distance to Persons: - far field Remarks: - power control Folie 6 Exposure of general public, November 07 Projects supported within DMF Development of measurement and calculation methods for the determination of the public exposure due to electromagnetic fields in the vicinity of mobile phone base stations (IMST) Determination of the exposure of groups of people that will be investigated within the scope of the project "Cross sectional study for ascertainment and assessment of possible adverse effects by fields of mobile phone base stations" (ECOLOG) Determination of the real field distribution from BS high frequency electromagnetic fields near UMTS transmitters (IMST+EM Institute) Folie 7 Exposure of general public, November 07 Extrapolated exposure (IMST+EM-Institute) 100,000 1.6 % limit GSM 5.4 V/m 10,000 0.7 % limit UMTS 78.3 mW/m² 5.1 V/m 69.3 mW/m² 1,000 0,100 0,010 power density in % of limit 0,001 0,000 1 2 3 4 5 6 7 8 9 1011 0.000001 % scenario no. 0.000001 % 0.004 V/m 0.01 V/m 0.03 µW/m² 0.1 µW/m² Folie 8 Exposure of general public, November 07 Extrapolated exposure near base stations (2) 100,000 high mounted antennas GSM 10,000 UMTS 1,000 0,100 0,010 power density in % of limit 0,001 0,000 1 2 3 4 5 6 7 8 9 1011 scenario no. low mounted antennas low mounted antennas (micro cell / indoor scenarios) Folie 9 Exposure of general public, November 07 Exposure ofgeneral public, November 07 Folie10 Comparison GSM/UMTS Comparison electric field strength [% of limit] 10 12 14 0 2 4 6 8 1.1 1.2 1.3 UMTS GSM 1.4 1.5 1.6 1.7 1.8 GSM 900 antenna pattern UMTS antenna pattern 1.9 1.10 1.11 1.12 1.13 1.14 1.15 1.16 1.17 1.18 1.19 1.20 1.21 1.22 2.1 measurement point point no. measurement 2.2 2.3 2.4 2.5 2.6 2.7 2.8 2.9 2.10 2.11 2.12 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9 3.10 3.11 3.22 3.13 3.14 3.15 3.16 3.17 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 Z (compared to limit) to (compared points all of 85% at >UMTS GSM Small scale field variation in space Measurement: GSM 900 and UMTS Simulation: GSM 900 100 95 90 85 80 electric field strength [dBµV/m] strength field electric 75 GSM 900 UMTS 70 0 20 40 60 80 100 120 140 place [cm] • Small scale variations (fast fading) especially at indoor scenarios due to multipath propagation • Variations of 10 dB and more Folie 11 Exposure of general public, November 07 Small and large scale variations in time Station A: GSM 24 hours Station B: GSM 7 days 4 2.0 3,5 1.8 3 1.6 2,5 1.4 2 1,5 1.2 electric field [V/m] strength electric field [V/m] strength 1 1.0 12:00 16:00 20:00 0:00 4:00 8:00 12:00 Tu We Th Fr Sa Su Mo Tu time day • Small and large scale variations due to traffic load (power control) Folie 12 Exposure of general public, November 07 Time and space averaged exposure (ECOLOG) Exposure inside buildings 1 m x 1 m grid 5 point grid • Time and space averaging, no focus on "maximal exposed areas" Z Exposure 10 - 1,000 times smaller than measured under worst case aspects Folie 13 Source: ECOLOG Institute Exposure of general public, November 07 Mobile phones Frequency: - 880 – 915 MHz (GSM 900) - 1710 – 1785 MHz (GSM 1800) - 1920 – 1980 MHz (UMTS) Transmit - up to 250 mW time averaged Power: - up to 2 W peak Number: - ~80 million Coverage: - up to 20 km Distance to Persons: - body contact Source: www.sonyericsson.com Remarks: - power control Folie 14 Exposure of general public, November 07 Exposure ofgeneral public, November 07 Folie15 SAR-Measurements • • SAR value 10g [W/kg] 0,2 0,4 0,6 0,8 1,2 1,4 1,6 1,8 0 1 2 typ. 10 –10 typ. consumption limit % 75 power) transmit (maximal conditions case" "worst is SARmeasured under Nokia N93 Sony Ericsson W550i Nokia E50 Nokia 6230i Sony Ericsson W700i Nokia 3250 Sony Ericsson K750i Sony Ericsson W810i Nokia 6233 Nokia 6270 Nokia 6131 Mobile phone Nokia N73 Sony Ericsson K510i Sony Ericsson W800i Nokia 6125 LG U8290 Samsung SGH-E770 Samsung SGH-X700 Siemens S75 Motorola ROKR Sagem my 700X BenQ-Siemens C81 BenQ-Siemens EF81 Motorola L7 Motorola V3x Pantech GU-1100 Palm Treo 650 Projects supported within DMF Determination of the specific absorption rate (SAR values) occurring during day- to-day mobile phone use (Telecom-Consult) Determination of the real exposure from using mobile phones in partially shielded rooms as compared to exposure under optimal conditions outdoors (Telecom-Consult) Folie 16 Source: Telecom-Consult Exposure of general public, November 07 Exposure results: Averaged exposure Inside a room, Nokia 6150 Inside a train, Nokia 6110/6150 Position change • On average 10 – 50 % of "worst case" SAR, depending on coverage and cell changes • Further reduction due to DTX Folie 17 Source: Telecom-Consult Exposure of general public, November 07 TV Broadcast Frequency: - 47 – 68 MHz (analogue) - 174 – 223 MHz (analogue, digital) - 470 – 790 MHz (analogue, digital) - 790 – 862 MHz (digital) Transmit - up to several 100 kW (ERP) Power: per site Transmitter:- typ. 5-15 main transmitters each federal state (Germany) Coverage: - up to 60 km Distance to Persons: - far field Wendelstein Folie 18 Exposure of general public, November 07 Projects supported within DMF Determination of exposure to the population living near digital radio and television transmitters (IMST+EM Institute) Folie 19 Exposure of general public, November 07 Exposure to Analogue TV and DVB-T (same region) Analogue TV DVB-T 100 100 10 10 1 1 0,1 0,1 0,01 0,01 0,001 0,001 0,0001 0,0001 power power density [% of limit] power density [% of limit] 0,00001 0,00001 0,000001 0,000001 0 50 100 150 200 250 300 350 0 50 100 150 200 250 300 350 measurement point measurement point • More than 300 measurement points in Nuremberg and Munich region • Points statistically distributed; proportional to population density • Measurements before (A-TV) and after (DVB-T) switching to DVB-T Z Exposures mostly below 0.01 – 0.1 % of limit Folie 20 Exposure of general public, November 07 FM radio and DAB Frequency: - 88 – 108 MHz (FM radio) - 174 – 223 MHz (DAB) - 1452 – 1492 MHz (DAB) Transmit - FM: typ. several 10 kW (ERP) Power: DAB: typ. several kW per site Transmitter:- several 100 (Germany) Coverage: - up to 60 km Distance to Persons: - far field www.zinsik.de Folie 21 Exposure of general public, November 07 Projects supported within DMF Determination of exposure to the population living near Hamburg digital radio and television Berlin transmitters (IMST+EM Institute) Düsseldorf Stuttgart München Folie 22 Exposure of general public, November 07 Exposure to FM radio and DAB (same region) FM radio DAB 100 100 10 10 1 1 0,1 0,1 0,01 0,01 0,001 0,001 0,0001 0,0001 power power density [% of limit] power density [% of limit] 0,00001 0,00001 0,000001 0,000001 0 50 100 150 200 250 300 0 50 100 150 200 250 300 measurement point measurement point • 300 measurement points in Nuremberg and Munich region • Points statistically distributed; proportional to population density Z Exposures mostly below 0.01 – 0.1 % of limit Z DAB exhibits ~11 dB lower exposure compared to FM radio (median) Folie 23 Exposure of general public, November 07 Long/Medium/Shortwave radio services Frequency: - 148 – 255 kHz (LW) - 0.526 – 1.6 MHz (MW) - 3.4 – 26 MHz (SW) Transmit - several 100 kW per site Power: (up to 2 MW) Transmitter:- several 10 (Germany) Coverage: - several 100 km Distance to Persons: - far field Folie 24 Exposure of general public, November 07 Exposure results Study by Wuschek et al., 2003 "Large area measurement of radio waves in Baden-Wurttemberg" 100 10 .