Early Influence by Cosmic Radiation -...
Transcript of Early Influence by Cosmic Radiation -...
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Radiation Exposure in Aviation Altitudes Radiation Exposure in Aviation Altitudes During Quiet and Solar Storm PeriodsDuring Quiet and Solar Storm Periods
Second European Space Weather Week, 14-18 November 2005 ESTEC, Noordwijk, The Netherlands
Peter Beck
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Early Influence by Cosmic RadiationEarly Influence by Cosmic Radiation
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Interaction of cosmic radiationwith atoms of a photographic film
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• 1911/1912: Hess-Strahlung• 1936: Nobel prize Hess, Anderson
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SCR particles in one second
• 5,000 per 1 m²• 400 / 4,000 => human body• 400 => laptop
• 250 / 2,500 => human body• 250 => laptop
• 10 / 100 => human body• 10 => laptop• 1,000 => car
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• Radiation exposure due to Cosmic Radiation - 50% low-LET (γ, e-, µ, …)- 50% high-LET (p, n, …)
1991: Updated Neutron weighing factorsICRP 60 recommendations for aircraft crew
1996: Council Directive 96/29/EURATOMArticle 42
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Studies & European Research Studies & European Research 19901990--2004: e.g. ACREM / DOSMAX 2004: e.g. ACREM / DOSMAX
•• ANPA / ItalyANPA / Italy•• ARCS / AustriaARCS / Austria•• AUA / AustriaAUA / Austria•• Brazilian Brazilian AirforceAirforce / Brazil/ Brazil•• CERN /SwissCERN /Swiss•• DIAS / IrelandDIAS / Ireland•• DLH AG / GermanyDLH AG / Germany•• DLR / GermanyDLR / Germany•• GSF / GermanyGSF / Germany•• INFN / ItalyINFN / Italy•• IPSN / FranceIPSN / France•• NPI / CzechNPI / Czech•• NRPB / UKNRPB / UK•• PTB / GermanyPTB / Germany•• SSI / SwedenSSI / Sweden•• TU TU -- Graz / AustriaGraz / Austria•• UniUni MMüünchennchen / Germany/ Germany•• University of Siegen / University of Siegen /
GermanyGermany•• VARIG / BrazilVARIG / Brazil
EURADOS in-flight radiation data base- 368 In-flight investigations- 10 526 Data sets analyzed
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WG5Considered In-Flight Investigation May 1992 – April 2003
EURADOS in-flight radiation data base: - 368 in-flight investigations- 10 526 data sets analyzed
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2004:2004: EURADOS EURADOS ECEC--ReportReport
ISOISO--StandardStandard: :
Dosimetry for exposure Dosimetry for exposure
to cosmic radiation in civil to cosmic radiation in civil
aircraft.aircraft.
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WG5EURADOS Working Group 5 on Aircraft Crew Exposure
D.T. Bartlett1, P. Beck2, P. Bilski3, J.-F. Bottollier-Depois4, L. Lindborg5 (Chairman from 2003), H. Schraube6, F. Spurný7 and F. Wissmann8, E. Felsberger9 (resigned in 2002), W. Heinrich10, B. Lewis11, D. O´Sullivan12, G. Reitz13, U. Schrewe14 (Chairman 2000 to 2002), and L. Tommasino15, G. Dietze8 for Article 31, I. McAulay16 for Article 31, J. Siedenburg17 (2004) and A. Ruge (2000 –2003) for JAA, K. Schnuer18 for EC and K. Ulbak19 for Article 31.
Contributions were also received from:J.C. Saez-Vergara(20), H. Roos(21), G.A. Taylor(22), R. Grillmaier(23), W. Friedberg(24), K. O’Brien(25), M. Pelliccioni(26), B. Wiegel(8) and their colleagues.
(1) National Radiological Protection Board (NRPB), Chilton Didcot, UK(2) ARC Seibersdorf Research (ARCS), Seibersdorf, Austria(3) Institute of Nuclear Physics, Krakow, Poland(4) Institute for Radiation Protection and Nuclear Safety (IRSN) , Paris, France(5) Swedish Radiation Protection Authority (SSI), Stockholm, Sweden(6) Forschungszentrum für Umwelt und Gesundheit (GSF), Institut für Strahlenschutz, Neuherberg, Germany(7) Nuclear Physics Institute, Academy of Sciences of Czech Republic, Prague(8) Physikalisch-Technische Bundesanstalt (PTB), Braunschweig, Germany(9) IASON Labormedizin GesmbH. & Co KG, Austria(10) Universität, Siegen, Germany(11) Royal Military College of Canada (RMC), Kingston, Ontario, Canada(12) Dublin Institute for Advanced Studies (DIAS), Dublin, Ireland(13) Deutsches Zentrum für Luft und Raumfahrt (DLR), Institut für Luft- und Raumfahrtmedizin, Köln, Germany(14) Fachhochschule, Hannover, Germany(15) National Agency for Environmental Protection and Technical Services (APAT), Rome, Italy(16) Trinity College, Dublin, Ireland(17) Central Joint Aviation Authority (JAA), Hoofdorp, The Netherlands(18) European Commission, DG TREN H4, Luxembourg(19) Statens Institut for Straalehygiejne (SIS), Knapholm, Denmark(20) CIEMAT, Dosimetría de Radiaciones, Madrid, Spain(21) Radiobiologisches Institut, Ludwig-Maximilians-Universität München, Germany(22) National Physical Laboratory, Teddington, U.K.(23) Fachrichtung Biophysik, Universität des Saarlandes, Homburg/Saar, Germany(24) Civil Aerospace Medical Institute, Federal Aviation Administration, Oklahoma City, USA(25) Northern Arizona University, Flagstaff, Arizona, USA(26) INFN, Laboratori Nazionali di Frascati, Frascati, Italy
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WG5Cosmic Radiation Exposure of Aircraft Crew:
Compilation of Measured and Calculated Data
Contents
Descriptions of calculation methodsAppendix B
Descriptions of measurement methodsAppendix A
Summary, conclusions and recommendationsChapter VI
Uncertainties in aircraft crew dose assessmentsChapter V
Comparison of calculated and measured route doses and selected dose rate data for scheduled flights
Chapter IV
Measured and calculated ambient dose equivalent rate data at aircraft altitudes
Chapter III
Cosmic radiation environment at aircraft altitudes and dosimetry
Chapter II
IntroductionChapter I
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Verification of Calculation CodesVerification of Calculation Codes
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17:00 18:00 19:00 20:00 21:00 22:00 23:00 00:00 01:00 02:00UTC
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ACREM
cum. TEPC
cum. ACREM
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ACREM
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cum. ACREM
Dose Rate
Route dose
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WG5
Altitude … standard barometric altitude / meter, (FL, feet)Latitude, Longitude … geomagnetic Latitude / degree
cut off rigidity rc / GVSolar activity … heliocentric potential HCP /MV
… solar deceleration potential SDP / MV
H = H (Altitude, Latitude, Longitude, Solar activity)H = H (Altitude, Latitude, Longitude, Solar activity)
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WG5
1998 – 200366TEPC LindborgSSI
1999342TEPCLewisRMC
199843Bonner Spheres, Ionization ChamberWiegelPTB
1997 – 19991240active instruments SchrewePTB
1997 – 200319track detectors and TLDsBartlettNRPB
2000-2003146TEPC TaylorNPL
2001811Si-spectra dosemeter (MDU-Liulin)SpurnyNPI
200249TEPCBottollier IRSN
1992 – 1993308active instruments Schraube, RegullaGSF
2001 – 20025680TEPC and other active instruments Saez-VergaraCIEMAT
1997 – 20031767TEPC and other active instruments BeckARCS
199755TEPC (tissue equivalent proportional
counter) and other active instrumentsTommasinoAPAT
Time PeriodNumber of data[1]
Dose assessment methodPrimary investigatorInstitute
[1] EURADOS In-Flight Radiation Data Base.
Analyzed In-Flight Investigations
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30 - 60 minBonner Spheres (BSS) and ionization chamber (IC) [WIE02], [BEC99a].BSS+IC (PTB)
5 minCombined neutron monitor LINUS with tungsten converter (NMX) and ionization chamber RSS (IC) [TOM99]
NMX+IC (APAT)
60 minTEPC (HANDI) [TOM99], [CUR01a], [CUR01b]TEPC (APAT)
30 minTEPC (HAWK) [BOT04]TEPC (IRSN)
single point calculationEuropean Program Package for the Calculation of Aviation Route Doses [SRA02]EPCARDv3.2
30 minTEPC (HAWK) [TAY02]TEPC (NPL-PPARC)
16 × 120 minBox with 36 PADC and 30 TL dosemeters [BAR00], [BAR01], [BAR03]Track Detector (NRPB)
30 minSi-Spectra-dosemeter developed originally for space (MDU-Liulin) [SPU03]LIULIN (NPI)
5 minCombined neutron monitor with tungsten converter (NMX) SWENDI-2 and ionization chamber (IC) RSS [SAE02] [ROM04] [SAE04a] [SAE04b]
NMX+IC (CIEMAT)
25 minTEPC (HAWK) [SAE02] [ROM04] [SAE04a] [SAE04b]TEPC (CIEMAT)
30 - 60 minTEPC instruments based on the variance method [KYL01]TEPC (SSI)
25 minTEPC (FAR WEST detector) [GRE00] [LEW01]TEPC (RMC)
30 - 60 minTEPC (HAWK) [BEC03], [BEC04]TEPC (ARCS)
30 – 60 minTEPC detector, 12 cm sphere, logarithmic amplifier [BEC99a], [BEC99b], [BEC04]TEPC-log (ARCS)
6 minCombined neutron monitor NE-NM2 with lead converter (NMX) and low level scintillation detector DLM7908 [REG93], [REG96]
NMX+Halle(GSF)
5 minCombined GM detector and transport code calculations [BEC99a], [BEC99b]ACREM (ARCS)
5 - 20 minCombined neutron monitor NE-NM2 with lead converter (NMX) and ionization chamber [SRE99a], [SRE99b]
NMX+IC (PTB)
5 minCombined neutron monitor (NM) LB6411 and ionization chamber (IC) RSS [BEC99a], [BEC99b]NM+IC (ARCS)
Measurement intervalsDose assessment methodmeasurement / calculation
Abbreviation
Dose Assessment Methods During In-Flight Investigations
TEPC (SSI) TEPC instruments based on the variance method [KYL01] 30 - 60 min
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A Tissue Sensitive InstrumentA Tissue Sensitive Instrument
•• TEPCTEPC (Tissue Equivalent Proportional Counter)(Tissue Equivalent Proportional Counter)•• Measures Measures absorbed doseabsorbed dose in 1 in 1 –– 2 2 µµm tissuem tissue
Electronics
Tissue equivalent chamber
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TEPC Simulation by FLUKATEPC Simulation by FLUKAMicrodosimetric Spectra in CR fieldMicrodosimetric Spectra in CR field
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-90 -80 -70 -60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60 70 80 90
Geomagnetic Latitude in Degree
Am
bien
t Dos
e Eq
uiva
lent
Rat
e in
µSv
/h
NM+IC (ARCS)
ACREM (ARCS)
TEPC (ARCS)
TEPC (SSI)
TEPC-log (ARCS)
NMX+Halle (GSF)
TEPC (RMC)
LIULIN (NPI)
NMX+IC (PTB)
Passive Detector(NRPB)
TEPC (NPL-PPARC)
TEPC (IRSN)
TEPC (APAT)
NMX+IC (APAT)
BSS+IC (PTB)
Avg. exp.
Altitude: 10 058m, (FL330)Solar activity: 470 MV - 610MV
Calculated Average Data
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-90 -80 -70 -60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60 70 80 90
Geomagnetic Latitude in Degree
Am
bien
t Dos
e Eq
uiva
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Rat
e in
µSv
/h
NM+IC (ARCS)
ACREM (ARCS)
TEPC (ARCS)
TEPC (SSI)
TEPC-log (ARCS)
NMX+Halle (GSF)
TEPC (RMC)
LIULIN (NPI)
NMX+IC (PTB)
Passive Detector(NRPB)
TEPC (NPL-PPARC)
TEPC (IRSN)
TEPC (APAT)
NMX+IC (APAT)
BSS+IC (PTB)
Avg. exp.
Altitude: 10 058m, (FL330)Solar activity: 610 MV - 750MV
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Geomagnetic Latitude in Degree
Am
bien
t Dos
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uiva
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Rat
e in
µSv
/h
IC+NMX (CIEMAT)
NM+IC (ARCS)
ACREM (ARCS)
TEPC (CIEMAT)
TEPC (ARCS)
TEPC (SSI)
TEPC-log (ARCS)
NMX+Halle (GSF)
TEPC (RMC)
LIULIN (NPI)
NMX+IC (PTB)
Passive Detector(NRPB)
TEPC (NPL-PPARC)
TEPC (IRSN)
TEPC (APAT)
NMX+IC (APAT)
BSS+IC (PTB)
Avg. exp.
Altitude: 10 058m, (FL330)Solar activity: 950 MV - 1140MV
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kilometer
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bien
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e Eq
uiva
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eµS
v/h
ACREM (ARCS)
BSS+IC (PTB)
IC+NMX (CIEMAT)
IC+SWENDI (RMC)
LIULIN (NPI)
NM+IC (ARCS)
NMX+Halle (GSF)
NMX+IC (APAT)
NMX+IC (PTB)
Passive Detector(NRPB)TEPC (APAT)
TEPC (ARCS)
TEPC (CIEMAT)
TEPC (SSI)
TEPC-log (ARCS)
TEPC (RMC)
TEPC (NPL-PPARC)TEPC (IRSN)
Avg. exp.
EPCARDv3.2
ARCS model
ARC-sr Model AVIDOS
Cutoff rigidity rc: 1 GVSolar activity: 470 MV - 610MV
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0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18Vertical Cut Off Rigidity
GV
Am
bien
t Dos
e Eq
uiva
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Rat
eµS
v/h
ACREM (ARCS)
BSS+IC (PTB)
IC+NMX (CIEMAT)
IC+SWENDI (RMC)
LIULIN (NPI)
NM+IC (ARCS)
NMX+Halle (GSF)
NMX+IC (APAT)
NMX+IC (PTB)
Passive Detector(NRPB)TEPC (APAT)
TEPC (ARCS)
TEPC (CIEMAT)
TEPC (IRSN)
TEPC (NPL-PPARC)
TEPC (RMC)
TEPC (SSI)
TEPC-log (ARCS)
Avg. exp.
EPCARDv3.2
ARCS code
ARC-sr Model AVIDOS
Altitude: 10 058m, (FL330)Solar activity: 470 MV - 610MV
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Frequency Distribution of Measured Frequency Distribution of Measured Ambient Dose Equivalent RateAmbient Dose Equivalent Rate
0%
5%
10%
15%
20%
25%
30%
35%
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Ambient Dose Equivalent Rate in µSv/h
Freq
uenc
y
EURADOS in-flight radiation data base: - 368 in-flight investigations-10 526 data sets analyzed- May 1992 – April 2003
1000 h … 2 - 3 mSv p.a.700 h … 1 - 2 mSv p.a.
Limit: p.a.20 mSv … occupational1 mSv … public
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0
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Ambient Dose Equivalent Rate in µSv/h
Two
Stan
dard
Dev
iatio
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s in
%
Uncertainty of Mean Ambient Dose Equivalent RateUncertainty of Mean Ambient Dose Equivalent Rate
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NewNew Aviation Dosimetry Model Aviation Dosimetry Model AVIDOSAVIDOS
•• ECEC--Project Project ACREM ACREM (2000) (2000) Aircraft Crew Radiation Aircraft Crew Radiation ExporsureExporsure MontoringMontoring
•• ECEC--Project Project DOSMAX DOSMAX (2004)(2004)Aircraft Crew Dosimetrie at Solar MaximumAircraft Crew Dosimetrie at Solar Maximum
•• ECEC--EURADOS EURADOS Report No140 Report No140 (2005) (2005) Cosmic Radiation Exposure of Aircraft Crew Cosmic Radiation Exposure of Aircraft Crew
•• FLUKA 2005FLUKA 2005
•• UpdatedUpdated primary proton spectraprimary proton spectra
•• EffectiveEffective dosedose
•• AmbientAmbient dose equivalentdose equivalent
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Calculated Effective Dose FL300 und FL550Calculated Effective Dose FL300 und FL550
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4 6 8 10 12 14 16
Flight altitude / km
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Ambi
ent d
ose
equi
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te /
µSv/
h
Equator regionPole region
Solarm axim um : minimum:
Radiation Exposure due to Cosmic Radiation Radiation Exposure due to Cosmic Radiation ((““Quiet PartQuiet Part””) )
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FixFix--installation in LH Airbus A340installation in LH Airbus A340
•• Solar Event:Solar Event:
April 2001April 2001 (GLE60)(GLE60)
•• Solar Storms: Solar Storms:
October / November 2003October / November 2003
GLE65, GLE66, GLE67GLE65, GLE66, GLE67
•• Solar Event:Solar Event:
January 2005January 2005
•• Literature: Literature: ~ 0,05 ~ 0,05 mSv/hmSv/h –– 1mSv/h1mSv/h
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October / November 2003:October / November 2003:Solar Storm TEPC measurementsSolar Storm TEPC measurements
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16,459 m (54,000ft)
11,887 m (39,000ft)
9,449 m (31,000ft)
GLE65 Forbush decreaseNormal periodReference Flight
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Risk Analysis by Epidemiological StudiesRisk Analysis by Epidemiological Studies
Chromosomal aberrationChromosomal aberrationChromosomal studyChromosomal study of Concorde pilots of Concorde pilots (2000)(2000)
Prostate cancerProstate cancer and acute leukaemiaand acute leukaemiaCanadian pilot Canadian pilot cohort study (1996)cohort study (1996)
No No significant significant increaseincrease of cancerof cancerGerman pilotsGerman pilots cohort study (2002) (M. cohort study (2002) (M. BlettnerBlettner))
Malignant melanoma and nonMalignant melanoma and non--melanoma melanoma skin cancerskin cancerNorwegian pilotNorwegian pilot cohort study (2000)cohort study (2000)
Breast cancerBreast cancerFinnishFinnish and and Danish cabin crewDanish cabin crew cohort cohort study (1995, 1996)study (1995, 1996)
Observed IncreaseObserved IncreaseStudyStudy
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Further Further ……
•• Lang, M., 2004Lang, M., 2004: : Radiation Exposure of Aircraft Crew Radiation Exposure of Aircraft Crew compared to radiological occupational compared to radiological occupational
–– based on based on BlettnerBlettner, UNSCEAR, Austrian data, UNSCEAR, Austrian data–– 1,22 1,22 mSvmSv ((±±1,2) p. a 1,2) p. a …… medical occupationalmedical occupational–– 1,43 1,43 mSvmSv ((±± 0,7) p.a. 0,7) p.a. …… aircraft crewaircraft crew
•• PelliccioniPelliccioni, M., et al., 2004, M., et al., 2004: : Comparison simulation free Comparison simulation free air / shielding by aircraft and passengerair / shielding by aircraft and passenger
–– 15%15% decreased for decreased for EE–– 25%25% decreased for decreased for H*(10)H*(10)
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ConclusionConclusion
•• Cosmic radiation leads to about Cosmic radiation leads to about 100 times100 times higher exposure higher exposure
compared on Earthcompared on Earth
•• Typical Typical 5 5 µµSv/hSv/h in 10 km altitudein 10 km altitude
•• Some Some studiesstudies showshow health hazardshealth hazards
•• Additional cancer risk small but evident:Additional cancer risk small but evident:
+1% +1% during during 35 years 35 years aircraft crew activityaircraft crew activity
•• Cosmic radiation exposure has to be Cosmic radiation exposure has to be assessed assessed inin EuropeEurope
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FutureFuture
•• Dose prediction due to ground relevant Dose prediction due to ground relevant solar events solar events
((ECEC--project CONRADproject CONRAD, WP6 Workplaces of mixed radiation fields), WP6 Workplaces of mixed radiation fields)
•• ISOISO--StandardStandard: : Dosimetry for exposure to cosmic radiation in civil Dosimetry for exposure to cosmic radiation in civil
aircraft (Part 1, 2, 3)aircraft (Part 1, 2, 3)
•• ICRU / ICRP TG 50: ICRU / ICRP TG 50: Aircraft Crew Dosimetry (International)Aircraft Crew Dosimetry (International)
•• EURADOS WG5:EURADOS WG5: Aircraft Crew Dosimetry (Europe) Aircraft Crew Dosimetry (Europe)
European Aircraft Crew Dosimetry Expert NetworkEuropean Aircraft Crew Dosimetry Expert Network
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AcknowledgementsAcknowledgements
The cooperation of EURADOS WG5 and support by The cooperation of EURADOS WG5 and support by AerAer LingusLingus, Air , Air Emirates, Air Canada, Air France, Air New Zealand, Emirates, Air Canada, Air France, Air New Zealand, AlitaliaAlitalia, Austrian , Austrian Airlines, British Airways, Czech Airlines, Airlines, British Airways, Czech Airlines, FinnairFinnair, Iberia, , Iberia, IcelandairIcelandair, , Lufthansa, NASA, Scandinavian Airlines System and VARIG is Lufthansa, NASA, Scandinavian Airlines System and VARIG is acknowledged. In some instances, unpublished results have been acknowledged. In some instances, unpublished results have been included of research partincluded of research part--funded by the European Commission, funded by the European Commission, DirectorateDirectorate--General Research, under the auspices of the European General Research, under the auspices of the European Commission RTD Commission RTD ProgrammeProgramme: Nuclear Energy (: Nuclear Energy (EuratomEuratom Framework Framework ProgrammeProgramme V, 1998V, 1998--2002) Contract N2002) Contract N°° FIGMFIGM--CTCT--20002000--00068. 00068.