Dr. rer.nat. Christian Felten BGF Institution for statutory accident insurance and prevention in the vehicle operating trades Hamburg, Germany

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1 Airport Security Screening Devices Possible Health Hazards due to Screening? Dr. rer.nat. Christian Felten BGF Institution for statutory accident insurance and prevention in the vehicle operating trades Hamburg, Germany

2 Contents Airport security screening devices to detect explosives or metal Physics Effects on People Limiting Values Technologies Physics Effects on People Limiting Values Technologies } } EMI X-rays Folie 2

People Limiting Values Technologies Physics Effects

3 Overview: Frequencies & Wavelengths Folie 3

4 Physical Units & Dimensions (Low Frequency LF) Variable Sign Unit induced by Electric field strength E [V/m] voltage Example: capacitor Magnetic field intensity H [A/m] current Example: magnetic coil Folie 4

5 Physical Units & Dimensions (LF) Electromagnetic induction B Tesla [T = Vs/m²] B = µ H Magnetic permeability µ Henry/m [H/m] in air: µ = H/m Electric current causes a magnetic field. The effect of the field on media is called electromagnetic induction. Folie 5

µ = 1.257 H/m Electric current causes a magnetic field.

6 Physical Units & Dimensions (LF) Electromagnetic induction B B = µ H Tesla [T = Vs/m²] Magnetic permeability µ Henry/m [H/m] in air: This is what we need for personnel security system µ = H/m Electric current causes a magnetic field. The effect of the field on media is called electromagnetic induction. scanners Folie 6

personnel security system µ = 1.257 H/m Electric current causes a magnetic field.

7 Predominant Fields Conditions Example Pred. Field low frequency (<30 khz) high voltage electric high voltage power line low current low frequency (<30 khz) low voltage high current passenger screening, electric motors, transformers magnetic high frequency (>30 khz) radar, microwaves, electro-magnetic radio (coupled) Folie 7

current low frequency (<30 khz) low voltage high current passenger screening,

8 Effects on People, EMI Low Frequency LF Stimulus of muscle-, nerve- and sense-cells (definite threshold) Hairvibration >5 kv/m Scintillation of eyes >5 mt (50 Hz) (magnetophosphenes) High Frequency HF Warming of the body (possibly deep: bypass of the receptors of skin) critical: eyes, ankles, patella, testes and metallic implants Influence on cardiac pacemakers Folie 8

(magnetophosphenes) High Frequency HF Warming of the body (possibly deep: bypass of the

9 Effects on People Non-thermic Effects of High Frequency Influence on brain-activities Interaction with cells/cell membranes Variation of immune system or hormone parameters Effect on blood-brain barrier Conclusion: There are little non-thermic effects, but there is no evidence for adverse effects Folie 9

system or hormone parameters Effect on blood-brain barrier Conclusion: There

10 Effects on People, EMI Cancerogenesis by EMI? Yes? Some (weak) hints from epidemiology Non-thermic effects without interpretation No? No accumulated dose No mechanism of cancerogenesis known If at all there are only a few case numbers Folie 10

11 Exposure Area 1: what does it mean? Danger Zone Gefahrenbereich pers. Schutzausrüstungen Area of higher Exposure Not: implication of danger, particularly with regard to short term exposure Kurzbereich 2h Exposure Area 1 Required: safety instructions and documentation (BGV B11) Expousre Area 2 Folie 11

particularly with regard to short term exposure Kurzbereich 2h Exposure

12 Examples for Reference Values, ICNIRP, Public Exposure High Frequency Immissions frequency (f) electric field strength magnetic field strength (MHz) (V/m) (A/m) 100: FM Radio 28 0, : Mobile (D-Net) 41,25 0, : Microwave oven 61 0,16 Low Frequency Immissions frequency (f) electric field strength magnetic induction (Hz) (kv/m) (µt) 50: Home appliances khz: Screening 0,087 6,25 Folie 12

(D-Net) 41,25 0,111 2450: Microwave oven 61 0,16 Low Frequency Immissions frequency (f) electric

13 Examples for Limiting Values BGV B 11 (occupational) High Frequency Immissions frequency (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 Immissions frequency (f) electric field strength magnetic induction (Hz) (kv/m) (µt) 50: Home appliances 6,67/21,32* 424/1358* 3-6 khz: Screening 0,333/1,066* 21,22/67,9* *Exposure area 2/1 Folie 13

2450: Microwave oven 61,5/137,3* 0,163/0,364* Low Frequency Immissions frequency (f) electric field strength magnetic

14 Air Passenger Security Screening System I Example: C.E.I.A. S.p.A. Italy, Type 02PN10 in Germany offered by Heimann Frequency 3-6 khz (LF) we need data of the electromagnetic induction (Tesla) (measured value and limiting value) Folie 14

15 Air Passenger Security Screening System II Measurement by Austrian Research Centers Seibersdorf 2001: <1,5 µt: side of the receiver 6,0 µt: in the middle max. 58,6 µt: side of the emitter in 40 cm height Limiting value (BGV B11): 21,22 µt (Area 2) 67,90 µt (Area 1), 169,75 µt for legs and arms And: very short time of exposure Folie 15

58,6 µt: side of the emitter in 40 cm height Limiting value (BGV B11): 21,22 µt

16 Air Passenger Security Screening System III Result: There is definitely no risk for members of staff or passengers incl. pregnant women or children There is no risk by repeated crossing of the scanners An influence on old or bad Cardiac Pacemakers is nervertheless possible: Folie 16

pregnant women or children There is no risk by repeated crossing of

17 What are potential EMI Hazards due to Screening? People with cardiac pacemakers or other active body adjuvants (possible interferences already in exposure area 2) Folie 17

18 X-Rays Another type of physics Folie 18

19 Physical Units & Dimensions (X-rays) X-rays are Ionizing Radiation! Absorbed dose D [Gy] in standardised tissue Equivalent dose H [Sv] D Q = H Radiation quality factor Q (α = 20 / β, γ, X-ray = 1) Equivalent dose rate [Sv/h] Effective dose E [Sv] E = Σ w i H i Tissue weighting factor w for every organ Local dose H*(10) [Sv] Folie 19

Radiation quality factor Q (α = 20 / β, γ, X-ray = 1) Equivalent dose rate [Sv/h]

20 Possible Effects on People, X-rays X-rays are Ionizing Radiation! High (cumulative) doses may cause cancer Very high doses may cause erythema or loss of hair This requires the main guideline of radiation protection: on principle ALARA: as low as reasonably achievable Folie 20

erythema or loss of hair This requires the main guideline of

21 X-rays: Limiting Values ICRP-Guidelines, in Germany RöV: effective Dose 20 msv/a for people with occupational radiation exposure, and 1 msv/a for public (and some more details) ICRP = International Commission on Radiological Protection Folie 21

22 Luggage Inspection, Systems for carry-on Luggage Employees nearby the X-ray unit: approx. 192 µsv/a [equivalent dose rate] Interior space, one passage: 0,5-2,1 µsv [local dose] 10 cm from the surface: 0,3 µsv/h [local dose rate] in front of lead lamella: 1,0 µsv/h [local dose rate] Measurement ( ): TÜV and Administration of Occupational Safety Hessen, several HEIMANN-Systems with X-Ray Photograph Folie 22

23 Systems for Suitcases and other checked Luggage e.g. Heimann Hi-Scan System 5 cm distance from surface (all around): < 0,1 µsv/h Folie 23

24 For Comparison Employees nearby the X-ray unit: approx. 192 µsv/a = 0,192 msv/a Radiography of teeth: approx. 0,1 msv Radiography of lumbar spine: approx. 5 msv Average natural background radiation in Germany: 2,5 msv/a Limiting value (public): 1 msv/a Folie 24

25 Detection of Critical Components of Luggage Visual Dogs Metal detection Neutron Activation Trace detectors (gas-chromatography, spectroscopy) Check of density X-ray diffraction for identification of substances like plastic explosives (e.g. Heimann or Yxlon International Security GmbH Hamburg, now a Company of General Electric, USA) X-ray Tomography (e.g. GE InVision, USA) m Folie 25

26 Special Technology for checked Luggage only CTX 5000-Series by InVision Technologies, Newark/Cal. (new name: GE InVision): X-ray computed Tomography + image processing software automated EDS (explosive detection system) with sliced pictures used in Europe, too Folie 26

27 Special Technology: Backscatter X-ray is a new imaging system, which detects the radiation which comes back from the target. e.g. for detecting weapons or people in containers or trucks e.g. for detecting suspicious objects carried nearby the body but under the clothing ( virtual strip search ) depth of impression is adjustable can be used as far as 50 m away from the target Folie 27 0,1 µsv per Scan is low, but mind the sum and ALARA

28 Other Technology: Neutron Activation Bombard suspicious luggage with neutrons and readγ-radiation decay signatures to determine the chemical composition of materials Rather a supplement for other primary screening procedures a) γ-radiation emitted and b) infinitesimal hot spots of radioactive atoms left behind, no data about doses Folie 28

29 Any Radiation Damage to the Luggage? No modification of food or pharmaceuticals No influence on data media or laptops Kodak found out damage to unprocessed films by the CTX- System (fogging). So take them in your carry-on luggage. Folie 29

30 Precautions: 3- D -Canon for Radiation Protection 1. Distance 2. Duration of stay 3. Degree of shielding The 4 th D for non-ionizing radiation and X-rays: Disconnect Folie 30

31 What are X-ray Hazards due to Screening? No acute health hazard for passengers or staff A small additional dose of ionizing radiation: remember ALARA Particular protection for pregnant women recommended Folie 31

32 Laser-Scanners for Luggage-Identification: Non-Ionizing Radiation Lasers of category 2 (BGV B2) might injure the eyes! There is no sufficient protection by the reflex of the eyelid! The first protection is prevention of exposure (no possiblity of looking straight into the beam), instruction of employees and - if necessary - special laser safety goggles Folie 32

33 The future Funny Times 2001 Folie 33

ELECTROMAGNETIC FIELDS AND PUBLIC HEALTH HEALTH AND SAFETY GUIDELINES #1

SINGAPORE, 16 AUGUST 2001 HEALTH SCIENCES AUTHORITY PRESS RELEASE ELECTROMAGNETIC FIELDS AND PUBLIC HEALTH HEALTH AND SAFETY GUIDELINES #1 THE EMF HEALTH ISSUE 1 Over the past years a large number of scientific