Risks due to EMI on Airports - Start – EAGOSH · Dr. Felten / BGF Hamburg 4 Physical Units & Dimensions Variable Sign Unit induced by Electric field strength E [V/m] voltage Example:

Risks due to EMIon Airports

Dr. rer.nat. Christian FeltenBGF(Institution for statutory accident insurance and prevention in thevehicle operating trades)

Hamburg, Germany

Dr. Felten / BGF Hamburg 2

Overview:

Frequencies & Wavelengths


Frequencies of Airport-Equipment

♦ RADAR e.g. 2,8 GHz (HF)

♦ Mobile phone 900 MHz (HF), D-Net

♦ Radio transmitter e.g. 160, 480 MHz (HF)

♦ Office-equipment 50 Hz (LF)


Physical Units & Dimensions

Variable Sign Unit induced by

Electric field strength E [V/m] voltage

Example: capacitor

Magnetic field intensity H [A/m] current

Example: magnetic coil


Electromagnetic induction B Tesla [T = Vs/m²]

B = µ • H

Magnetic permeability µ Henry/m [H/m]

in air: µ = 1.257 H/m


Electric current causes amagnetic field. The effect ofthe field on media is calledelectromagnetic induction.


Electromagnetic Induction - Example (male)

0 µT 15-1500 µT

Electric razors high electromagnetic induction is caused bya) electric motor and b) short distance to skin


... Example (female)

6-2000 µT (3 cm distance)


Typical Values - Low FrequencyLimiting value (50 Hz): 424 µT (BGV B11);

100 µT (26. BImSchV)Distance Magnetic induction

Monitor 3 cm 0,5-10 µTMonitor 30 cm 0,1-1,0 µTComputer 3 cm 0,5-3,0 µTComputer 30 cm <0,01 µTCoffee machine 3 cm 1,0-2,0 µTRefrigerator 3 cm 0,5-1,7 µTTable lamp 3 cm 0,1-0,2 µT



Power density, emittance S = E • H [W/m²]

Example: electrotherapy = max. 630 W/m²

applicability: instrument for electrotherapy (leimcke physiotherm®)

Effect on body:

Specific absorption rate SAR [W/kg] -Transfer of heat/energy; depends onstrength of emittance S and onphysical/electrical properties of recipient


Predominant FieldsConditions Example Pred. Fieldlow frequency (<30 kHz) high-voltage- electrichigh voltagevoltagevoltagevoltage power-linelow current

low frequency (<30 kHz) transformators, magneticlow voltage electric motors,high currentcurrentcurrentcurrent el. welding unit

high frequency (>30 kHz) radar, microwaves, electro-magneticradio (coupled)


Effects on People

Low FrequencyLow FrequencyLow FrequencyLow Frequency LF LF LF LF• Stimulus of muscle-,

nerve- and sense-cells(definite threshold)

• Hairvibration >5 kV/m• Scintillation of eyes

>5 mT (50 Hz)(magnetophosphenes)

HighHighHighHigh Frequency Frequency Frequency Frequency HF HF HF HF• Warming of the body

(possibly deep:avoidance of thereceptors of skin)critical: eyes, ankles,patella, testes andmetallic implants

•Influence on cardiac pacemakers


Effects on PeopleNon-Non-Non-Non-thermic effectsthermic effectsthermic effectsthermic effects of High of High of High of High Frequency Frequency Frequency Frequency

• Influence on brain-activities• Promotion of sleep, but suppression of

REM-phases by mobiles• Possibly audible pulses• Production of heat shock proteins in

nematodes by low level HF-radiationConclusion: even if many assumptions are

unproved: there are non-thermic effects,but we are not yet able to interpretethem in regard to human health


Effects on People

Yes?• Some (weak) hints

from epidemiology• Athermic effects

without interpretation

No?• No accumulated dose• No mechanism of

cancerogenesis known• If at all there are only

small case numbers

Cancerogenesis by HF-Radiation?

Conclusion:• A cancerogenesis by HF-radiation is not published• But we don´t know much about long-time exposure


Precautions:3-„D“-Canon for Radiation Protection

• 1. DDDDistance

• 2. DDDDuration of stay

• 3. DDDDegree of shielding

• The 4th „D“ for non-ionizingradiation:DDDDisconnect


Dependency on DDDDistanceMagnetic induction is subject to distance; quadratic dependency


Examples for Limiting ValuesRec. of ICNIRP, IRPA, SSK

High Frequency EmissionsFrequency (f) electric field strength magnetic field strength

(MHz) (V/m) (A/m)100: FM Radio 27,5 0,073900: Mobile (D-Net) 41,25 0,1112450: Microwave oven 61 0,16

Low Frequency EmissionsFrequency (f) electric field strength magnetic induction

(Hz) (kV/m) (µT)50: Home appliances 5 10016,67: Rail 10 300


Examples for Limiting Values → BGV B 11 (for workers)

High Frequency EmissionsFrequency (f) electric field strength magnetic field strength

(MHz) (V/m) (A/m)100: FM Radio 27,5/61,4* 0,073/0,163*900: Mobile (D-Net) 41,25/92,1* 0,109/0,244*2450: Microwave oven 61,5/137,3* 0,163/0,364*

Low Frequency EmissionsFrequency (f) electric field strength magnetic induction

(Hz) (kV/m) (µT)50: Home appliances 6,67/21,32* 424/1358*16,67: Rail 20/30* 1273/4073*

*Exposure area 2/1


Danger ZoneDanger ZoneDanger ZoneDanger Zone

Area of Area of Area of Area of higherhigherhigherhigher Exposure Exposure Exposure Exposure

Exposure - Area 1Exposure - Area 1Exposure - Area 1Exposure - Area 1

Exposure - Area 2Exposure - Area 2Exposure - Area 2Exposure - Area 2

2 hours

Danger Zone - only with protective equipment

Limiting Values „Area Concept“ in BGV B 11


Limiting ValuesBGV B11 - Electric Field


Limiting ValuesBGV B11 - Magnetic Field


Typical Values - Low FrequencyLimiting value (50 Hz): 424 µT (BGV B11);

100 µT (26. BImSchV)Distance Magnetic induction

Monitor 3 cm 0,5-10 µTMonitor 30 cm 0,1-1,0 µTComputer 3 cm 0,5-3,0 µTComputer 30 cm <0,01 µTCoffee machine 3 cm 1,0-2,0 µTRefrigerator 3 cm 0,5-1,7 µTTable lamp 3 cm 0,1-0,2 µT


Typical Values - High Frequency

Distance Power density Limiting valueBGV B11, Area2

FM-Radio-tower 1500 m <0,05 W/m² 2 W/m²Mobile ph. 900 MHz 3 cm <2 W/m² 4,5 W/m²Transmitter 900 MHz 50 m 0,001 W/m² 4,5 W/m²Office under transmitter 0,009 W/m² 4,5 W/m²Microwave-oven 5 cm 0,62 W/m² 10 W/m²Airport-Radar 100 m 0,1-10 W/m² 10 W/m²Traffic-Radar 30 cm 1-8 W/m² 10 W/m²


Standortbescheinigung („locationcertificate“) for RADAR-Set

Contains only a calculated value forsafesafesafesafe distance distance distance distance (no measurementresults!)

Example ASR- 2000-Radar:168 m in mainbeam direction

2,8 GHz → 61 V/mlimiting value • 32= 1952 V/m

Base: worst case calculation by

• limiting value 26. BImSchV forpulsed radiation (factor 32 [§2step2])

• peak capacity (power of the set)

• neglect of rotation(time)


Apron and ramp vehicles


What about EMI byradio transmitters?


Results of Own Measurements:Apron and Ramp Vehicles, Radio Transmitter

Antenna on top of the vehicles, 20 cm distance160 MHz max. 50 V/m, max. 160 mA/m418 MHz max. 32 V/m, max. 66 mA/m In the vehicle, door open160 MHz max. 7,5 V/m418 MHz max. 4,5 V/m

Charging station for radio transmitter - 1,5 µT (30 cm/50 Hz)

} ExposureArea 1


Exposure Area 1: what does it mean?

Not: implication of danger,particularly with regard to shortterm exposure

Required: safety instructionsand documentation (BGV B11)


→ ... has to be investigated!


What are Potential Radiation Hazards?

• Stay close to RADAR: normally improbable close enough to airport-RADAR, but possibly close enough to aircraft-RADAR during maintenance/testing („passive“ exposure)• Maintenance of RADAR („active“ exposure of stuff)• People with metallic implants or cardiac pacemakers (possible interferences by LF or HF already in exposure area 2)? Not really known effects of long-term use of mobiles or radio sets

BGF plans to determine safedistance throughmeasurements this year


RADAR and Cancer by X-Ray?Risk of cancerogenesis by EMI is notnotnotnot documentated!

Imaginable (only under special circumstances) is acancerogenesis due to Ionizing Radiation (X-ray)from a HF-generator (tubes)


X-Ray Doses

Worst case example: Klystron-tube 101 kV→ On the surface of the tube: ca. 40 µSv/h→ In working position (maintenance): max 1,1 µSv/h

Exposure about 360 h/a leads to 396 µSv/a annual dose

Reference values:

New german radiation protection ordinance: 1000 µSv/a

Average natural background radiation in Germany: 2500 µSv/a


Units & Dimensions

Absorbed dose D [Gy] Equivalent dose H [Sv] D • Q = H Radiation weighting factor Q

Equivalent dose rate [Sv/h]


Source of Ionizing Radiation:Airport X-ray for Luggage-Inspection

LuggageLuggageLuggageLuggage----inspection systems ofinspection systems ofinspection systems ofinspection systems of Düsseldorf International Airport Düsseldorf International Airport Düsseldorf International Airport Düsseldorf International Airport

5 cm distance from surface (allaround): < 0,1 µSv/h

Exemplary measurement of theinside dose in „HeimannHi-Scan“ Systems: 0,5 - 2,1 µSv

(Measurement by TÜV and a privatecompany)


Laser-Scanners for Luggage-IdentificationNon-Ionizing Radiation:

Even Lasers of category 2 (BGV B2) mightinjure the eyes!

There is no sufficient protection by the reflexof the eyelid!

The first protection is prevention of exposure(no possiblity of looking straight into thebeam),instruction of employees and- if necessary - special laser safety goggles

A measurement is projected


Conclusions• Strong dependence on frequencies: limit values,

protection measures and ev. biological effects• Radiation protection is essential in case of

maintenance of RADAR and if people use cardiacpacemakers

• The ubiquitary exposure don‘t lead to danger:Normally fear induces illness, not the radiation!

• Some questions still have to be clarified:♦ long term effects of mobile radiation?♦ safety margin to aircraft RADAR?♦ danger by laser-scanners?


Thanks to

U. Metzdorf(while repairing laboratory devices)

E. Willer(while sampling dust probes)


Conclusion (2)

„Too much radar“ may be harmfulunder several circumstances ...

... but insufficient radar may be, aswell!

Documents

Risks due to EMI on Airports - Start – EAGOSH · Dr. Felten / BGF Hamburg 4 Physical Units & Dimensions Variable Sign Unit induced by Electric field strength E [V/m] voltage Example: