B.J. LewisB.J. LewisRoyal Military College of CanadaRoyal Military College of Canada

Ottawa Chapter, Canadian Nuclear SocietyOttawa Chapter, Canadian Nuclear SocietyOttawa, OntarioOttawa, OntarioApril 16, 2009April 16, 2009

Aircrew and Spacecrew Radiation Exposure The Dangers of Getting High

Outline

Aircrew Radiation Exposure Assessment Measurements and Computer Code Development

Space Radiation Monitoring

Typical Annual Radiation Exposure

Total Average Annual Exposure 3.6 mSv

Impetus

ICRP-60 (1990) and ICRP-103 (2007): Reduce radiation exposure limits:

Nuclear Energy Worker (NEW): 50 to 20 mSv/year Public: 5 to 1 mSv/year

Recognize occupational exposure of aircrew to radiation

Aircrew Radiation Regulation

European Union (Basic Safety Standard Directive, May 2000)

Canada(Transport Canada, Commercial and Business Aviation Advisory Circular, April 2001) Account for exposure for >1 mSv/y (> 8 km)

Assess exposure Adjust working schedules (> 6 mSv action level) Inform workers Control doses during pregnancy (

P. Band et al., B.C. Cancer Foundation (Cdn/AC Pilots, 1950-1992) Excess AML and prostatic cancer

J. Grayson et al., Brooks AFB (USAF Pilots, 1975-1989) Excess cancer in all sites, testis & urinary bladder

E. Pukkala et al, Finnish Cancer Registry (FAs, 1967-1992) Excess female breast and bone cancer

European Study of Cancer Among flying PErsonnel (ESCAPE) (9 countries) (1960-1997) Scarce evidence for specific occupational cancer risk Revised interest with ESCAPE II (or COSMIC) study to include US PAN AM cohort

D. Irvine, British Airways Pilots, 1998 B. Grajewski, NIOSH Studies (FA (1998-2000), Pilots (2001))

FAs reproductive health effects Biomarker study of pilots

Epidemiological Studies

Radiation Exposure to Aircrew

Complex mixed-radiation field

Galactic Cosmic Rays (GCR)

Solar Particle Events(SPE)

Galactic Cosmic Ray (GCR) Exposure Conditions

Relatively constant field dependent upon: Solar Activity Latitude Altitude

Complicated field Many particle types, large energy range Greater uncertainty in biological risk

Solar Magnetic Field Shielding (When)

GCR intensity GCR intensity anticoincidentanticoincident with solar cyclewith solar cycle

0

50

100

150

200

250

300

350

400

1953 1958 1963 1968 1973 1978 1983 1988 1993 1998 2003 2008

Year

Suns

pot N

umbe

r

1500

2000

2500

3000

3500

4000

4500

Clim

ax H

ourly

Cou

nt R

ate

/100

19 20 21 22 23

Earth Magnetic Field Shielding(Where)

Greater shielding at equator than geomagnetic poles (factor of ~3)

Atmospheric Shielding(How High)

Satellite

Balloon

Supersonic

Subsonic

High Peaks

AtmosphericNucleus

40 km

20 km

10 km

1 km

MNS

LET Chamber

NE213 Scintillator

Anthropomorphic Phantomwith TLDs and BDs

BGOScintillators

Detector NIMs, Computers, UPS

LLRM

Equipment Suite Development

Commercial Aircraft Measurement

TEPCTEPC SWENDISWENDIEberlineEberline

NRDNRD

SWENDISWENDI Ionization Ionization ChamberChamber

Aircrew Radiation Studies

Experimentation ~250 Flights (Portable Instruments)

Ionization Counter/Al2O3 TLDs (low-LET) SWENDI Remmeter/Bubble Detectors (high-LET) Liulin-4N and 4SN (Si-based) LET Spectrometers Tissue Equivalent Proportional Counter (Hawk TEPC)

Model/Code Development Predictive Code AIrcrew Radiation Exposure (PCAIRE)

0

20

40

60

TEPC IC TLD SWENDI BD

TOTAL = NEUTRONIONIZING +

Ambient Dose Equivalent Distribution (Sv)

GammaGamma

XX--RayRay

ElectronElectron

Ionizing Ionizing (low(low--LET)LET)

NeutronsNeutrons(high(high--LET)LET) 2020

11

11

11

Quality Factor

Aircrew

Q=138%

Q>162%

US Atomic Radiation Workers

Q=20 Lung4%

Q=193%

Q>1 Other3%

Global Flight Group FlightTime (h)

Total DoseEq. (Sv)

Trans-Pacific (CYVR-KIX)Trans-Atlantic (CYYZ-LHR)Trans-Canada (CYYZ-CYVR)Caribbean (BGI-CYYZ)Northwest/Yukon (CYOW-CYFBCYRB-CYSR-CYFB-CYOW)

10.2 6.5 5.0 5.710.2

57 939 635 527 4

54 28

2.2 0.42.5 0.42.4 0.42.2 0.43.4 0.6

TEPC Data from Selected Flight Routes

Q

Data Coverage

HNL

LP PDDIAP

PGUA

TEPC Count Rate

0

500

1000

1500

2000

2500

0:00 1:00 2:00 3:00 4:00 5:00 6:00 7:00Time (Z)

Cou

nt R

ate

(Cou

nts/

Min

)

19:00 20:00 21:00 22:00 23:00 0:00 1:00 2:00Time (Z)

0

5000

10000

15000

20000

25000

30000

35000

40000

Altit

ude

(ft)

Heading North

Constant Latitude

YGK-YYZ-HGK Polar Flight (2005)

YGK-YYZ YYZ-HGK (polar) HGK HGK-YYZ YYZ-YGK

Toronto to Hong Kong Hong Kong to Toronto

4/18/05 9:00 4/18/05 21:00 4/19/05 9:00 4/19/05 21:00 4/20/05 9:00 4/20/05 21:00

Date and Time

0

2000

4000

6000

8000

10000

12000

Alti

tude

(m)

IC+SWENDIHAWKFH41BLiuLinFH41B CorrectedFlight Altitude

0.1

1

10

Am

bien

t Dos

e E

quiv

alen

t Rat

e (u

Sv/

h)

TEPC Data Analysis

Geomagnetic latitude calculated from geographic latitude & longiGeomagnetic latitude calculated from geographic latitude & longitudetude

Geomagnetic Latitude, Bm (deg)

-45 -30 -15 0 15 30 45 60 75 90

Ambi

ent T

otal

Dos

e E

quiv

alen

t Rat

e, H

(S

v/h)

0

2

4

6

8

10

12

14

169.4 km10.0 km (+2 Sv/h)10.6 km (+4 Sv/h)11.2 km (+6 Sv/h)11.8 km (+8 Sv/h)Best Fit at 10.6 km

.

Latitude Dependence:Dose Rate Vs Cutoff Rigidity

Ambient dose equivalent rate (35000 ft)

Cutoff Rigidity, Rc (GV)0 2 4 6 8 10 12 14 16 18

Am

bien

t Dos

e E

quiv

alen

t Rat

e (

Sv/

h)

0

2

4

6

8

10

NorthSouthBest Fit

.

GCR ability to penetrate magnetic GCR ability to penetrate magnetic fieldfield

Global CutoffRigidity Contours

Altitude Effect (Balloon Flights)

Satellite

Balloon

Supersonic

Subsonic

High Peaks

AtmosphericNucleus

40 km

20 km

10 km

1 km

Atmospheric Depth h (g / cm2)

0 200 400 600 800 1000f A

lt0.01

0.1

1

10

Balloon Data (July 14, 2001)Balloon Data (July 23, 2001)Model

Solar Cycle Effect (10.7 km)

Vertical cutoff rigidity Rc (MV)0 2 4 6 8 10 12 14 16 18

Ambi

ent d

ose

equi

vale

nt ra

te (

Sv/

h)no

rmal

ized

to 1

0.6

km

0

2

4

6

8

RMC IC+SWENDI (Climax = 3744 counts/h/100, = 984 MV)ACREM IC+NMX (Climax = 4277 counts/h/100, = 498 MV) Best Fit ACREM IC+NMXBest Fit RMC IC+SWENDI

Poles Equator

IC + SWENDI

PCAIRE Code

Visual_PCAIRE.exe

PCAIRE Code vs Concorde/ER-2 (NASA) (High-Altitude)

15.2 -18 km (Concorde)15.2 - 21 km (ER-2)

PCAIRE Predicted Route Dose (Sv)0 20 40 60 80 100 120 140 160

TEPC

Mea

sure

d R

oute

Dos

e (u

Sv)

0

20

40

60

80

100

120

140

160Heliocentric Potential (FAA)Deceleration Parameter (NASA)

Concorde Flights

ER-2 South 1 & 2

ER-2 East

ER-2 North 2

ER-2 North 1

Aircrew Annual Exposure

0

1

2

3

4

5

6

Flight Attendants Pilots

PC-A

IRE

Pred

ictio

n of

Ann

ual

Dos

e Eq

uiva

lent

(mSv

)

ICRP 60 Public Limit

99-EHD-239

0

2

4

6

Ave

rage

Exp

osur

e (m

Sv/y

ear)

Occupation

Nuclear FuelHandlerIndustrialRadiographerUranium Miner

Nuclear MedicineTechnologistCommercialAircrew

Canadian Annual Occupational Exposures

Health Impact

~25% of population will develop fatal cancer If aircrew exposed to 6 mSv/y over 30 years, risk of

developing a fatal cancer: 6 mSv/y x 30 y x 4 x10-5 cancers/mSv = 0.7%

Radiation Exposure from Solar Particle Events (SPE)

Highly sporadic events associated with solar flares and coronal mass ejection

Additional exposure to aircrew

Aircrew Exposure from SPEs

Propagate GCR and GOES-11 spectra (p, He) through atmosphere with Monte Carlo Code (MCNPX)

Prot

on F

lux

(n/M

eV/s

r/cm

2 )

Proton energy (MeV)

SPE

GCR

Dose and NM Count Rate Prediction

( ) ( )

( ) ( )

=

= =+

=

= =+

=

=

=

=

m

ii

primEiNM

m

i

n

j

primiEijjii

m

ii

primEiA

m

i

n

j

primiEijjii

EEPh

sPREcC

EEPPKEcH

1,

1 1,1,

1

1,

1 1,1,

1

3600)hcount (

hs3600)h Sv(,E

&&&

&&&&

NM Count Rate

Dose Rate

Energy bin width

NM Response Function

MCNPX matrix coefficients

Primary GOES spectrum

Dose Conversion Coefficient

Global Cut-off Rigidity Contours

Noisy Sun Effects

Solar Storm Effects and Solar Flare Anisotropy

"SOHO (ESA & NASA)"

Neutron monitor peak count rate - April 15th, 2001

1.E-01

1.E+00

1.E+01

1.E+02

1.E+03

1.E+04

100 1000 10000

Effective Cutoff Rigidity (MV)

Cou

nt R

ate

(C/s

)

RMC Model (0 km) Thule OuluCape Schmidt Lomniky Stit MagadanIrkutsk Alma Ata ApatityJungfraujoch Kiel NewarkRome Yakutsk RMC Model (3 km)South Pole

RMC Model (0 km)

RMC Model (3 km)

Neutron Monitor Analysis

SPE Aircrew Exposure (GLE 60)

0

2

4

6

8

10

12

14

16

18

10 11 12 13 14 15 16 17 18 19 20

GCR (background)(PCAire v7.2)

SPE Model

Measurements (MDU)

Prague JFK International, NY

Start of Solar Flare

Am

bien

t Dos

e R

ate

(Sv

/hr)

Universal Time (UTC) * Spurny et al

(April 2001)

Commercial Code Development: PCAIRESys Operational environment:

Not for Research Monitoring system for large number of personnel and flights

AirlineHuman

resourcesdatabase

AirlineHuman

resourcesdatabase

PCAIREPCAIRESysSysDose databasedose by flightdose by crew

Interface

Pcairesystem

administrator

Employees

Employer

National Dose Registry

Databaseadministrator

Sources of Space Radiation (Manned Missions in Low-Earth Orbit)*

S

N

SOUTH ATLANTIC ANOMALY(Protons)

INNER RADIATION BELT(Protons)

OUTER RADIATION BELT(Electrons)

OUTER RADIATION BELT(Electrons)

GALACTIC COSMIC RADIATION (GCR)(Protons to Iron Nuclei) Magnetic

AxisSpinAxis

* Adapted from: M. Golightly, Radiation Familiarization, CSA Training with SRAG, NASA, JSC, January 27-31, 2003.

SOLAR PARTICLE EVENT(Protons to Iron Nuclei)

Nominal In-flight Radiation EnvironmentElectrons in outer radiation beltGalactic Cosmic Rays

Protons in South Atlantic Anomaly

Space Weather Radiation Enhancements

Outer electron belt enhancement--electrons

Solar particle event (SPE)--protons

Additional radiation belts-- high energy electrons, protons (?)

Parameters that Affect Exposure or Susceptibility

Mission Factors Space Weather Orbit Inclination South Atlantic Anomaly (SAA) Passage Altitude Shielding Length of Mission

Individual Factors Sex Age Health Status Nutritional Status Ethnicity

IV-CPDSTEPCRAMsCPDs

TEPCPRDsCPDs

EV-CPDSEV-CPDS: Extra-Vehicular Charged Particle Spectrometer

IV-CPDS: Intra-Vehicular Charged Particle Spectrometer

TEPC: Tissue Equivalent Proportional Counter

RAM: Radiation Area Monitors(TLDs)

PRD: Passive Radiation Dosimeter(TLDs)

CPD: Crew Passive Dosimeter (TLDs, PNTD)

Active instrument real-time telemetry

Active instrumentno real-time telemetry

Passive instrument

Space Radiation Monitoring

* Adaped from: M. Golightly, Initial Briefing to Astronauts Radiation Exposure During Space Missions, 1998 Astronaut Candidate Class, NASA-JSC, June 10, 1999.

Space Dosimetry* Type Program Measurements

Crew Personnel Dosimetry:TLD-100 All Programs Absorbed doseTLD-300, 600, 700 STS, and ISS Absorbed doseCR-39 or other Nuclear plastic track detectors

Apollo, Skylab, STS, STS, Mir Fluence vs. LET or Z

Fission Foils Apollo, STS Neutrons

Area dosimetry:TLD-100 STS, Mir, ISS Absorbed doseTLD-300, 600, 700 STS, ISS Absorbed doseCR-39 or other Nuclear plastic track detectors Fluence vs. LET or ZFission Foils Apollo, STS NeutronsActive Ionization Chambers Apollo, Skylab Absorbed doseTEPC STS, Mir, ISS Lineal energy, dose, dose equivalentZ,E Telescope Mir, STS, ISS Fluence vs. Z and EBonner Spheres STS, ISS NeutronsBubble detectors STS Neutrons

*Adapted from: F. Cucinotta, Organ Dose Estimates for Astronauts, CSA Training with SRAG, NASA-JSC, January 27-31, 2003.

Typical Exposures Daily Exposures

150 200 Gy/d (solar max) (2 x greater at solar minimum)

25 mGy or ~ 60 mSv for 140 days (CNSC terrestrial limits are 20 mSv/y)

Dependent upon where you spend your time/sleep/timing/altitude etc.

SPE Doses (IVA) Highly variable

Small events ~100 200 Gy ( ~ 300 Gy @ TEPC/Lab Fwd)

Large events ~ 10 20+ mGy (Jul 2000 estimate ~6 mGy @ Node1)

Radiation Exposure ComparisonsType of Exposure Limit: Annual Canadian Public Limit: Annual Canadian Radiation Worker

Average annual exposure to natural background Average annual occupational exposure (US) (ground) Living one year in Kerala, India

Airline Flight Crew

Apollo 14 Highest Skin Dose Average Shuttle Skin Dose STS 82 Highest Skin Dose STS-57 (473 km, 28.5) STS-60 (352 km, 57) 140 day mission on ISS (400 km, 51.56) 1 year in deep space (5 g cm-2 Al shielding) 1 year deep space (5 g cm-2 polyethylene shielding) Mars mission BFO Dose (GCR+SPE: behind 10 g cm-2 shielding) (3-year)

Dose Equivalent1 mSv/y

20 mSv/y

2.94 mSv/y2.10 mSv/y13 mSv/y

1-6 mSv/y

14 mSv~4.33 mSv76.3 mSv19.1 mSv

4 mSv~60 mSv1140 mSv870 mSv

800 to 2000 mSv

Biological Effects of Ionizing Radiation

Ionizing radiation causes atoms and molecules to become ionized or excited: Produce free radicals Break chemical bonds Produce new chemical bonds and cross-linkage between macromolecules Damage molecules that regulate vital cell processes (e.g. DNA, RNA, proteins).

Tissues that undergo rapid cell regeneration are most sensitive to radiation (e.g., blood-forming organs, reproductive organs, and lymphatic system)

U.S. Astronaut Exposure Limits

Exposure Duration

Blood Forming Organs Eye Skin

30 days 0.25 1.0 1.5

Annual 0.50 2.0 3.0

Career Limit: fatal cancer (3% for all ages and both sexes)

National Council on Radiation Protection and Measurements (NCRP), Guidance on Radiation Received in Space Activities. NCRP Report No. 98, (July 31, 1989)

NCRP Report No. 132 (Dec 2000)

Career Exposure LimitsNCRP Report No. 98 (1989)

(Sv)

10 Year Career Exposure LimitsNCRP Report No. 132 (2000)

(Sv)

Age (yr) Male Female Male Female

25 1.5 1.0 0.7 0.4

35 2.5 1.75 1.0 0.6

45 3.25 2.5 1.5 0.9

55 4.0 3.0 3.0 1.7

Non-Stochastic (Deterministic) Effects: NCRP-98 (Sv) and NCRP-132 (Gy-Eq)*

*NCRP-132 uses relative biological effectiveness (RBE) in place of quality factor (Q)

Observed Astronaut Health Effects (Hamm & Al 2000)

Significant increase in lifelong risk of cataracts in astronauts Of 48 lens opacities in 295 astronauts, 39 of those occurred after space flight 90% of those 39 cataracts occurred after lunar missions and high inclination space flights

14 cases of cancer in 312 astronauts from 1959 to present (excluding non-melanoma skin cancers)

59% higher than the control group

No protection from Earths magnetic field

image from NASA/Viking

Interplanetary Travel

Summary

Aircrew RadiationPCAIRE Code Development (GCR and Solar Flares)

Experimentally-based - Only one!Commercial Airline Application (spin off) (PCAIRESys)

Space Radiation

AcknowledgementsRMC Research Team: Prof. L. Bennett, Research Associates and Assistants (A.R. Green, A. Butler, M. Boudreau, B. Bennett), Graduate Students (Dr. P. Tume, M. McCall, B. Ellaschuck, M. Desormeaux, Dr. M. Pierre, H. Al Anid) Air Canada, Canada 3000 Airlines, Canadian Airlines International, Canadian Regional Airlines, First Air, Aerolinas Argentinas, British Airways, Air Operations at 8 Wing Trenton, 437/436/429 SquadronsJ. Servant (Transport Canada),C. Thorp & S. Kupca (DGNS/DND), W. Friedberg (US Federal Aviation Administration), H. Goldberg (Air Transport Association of Canada), M. Pelliccioni & A. Zanini (INFN), E. Felsberger (U Graz), S. Roesler(CERN), A. Chee (Boeing), H.Schraube (GSF), W. Heinrich (U Siegen), K. OBrien (Northern Arizona U), U. Schrewe (FHH), D. Bartlett (NRPB), V. Ciancio (UNP), D. Irvine (British Airways), J. Lafortune and F. Lemay (PCAIRE Inc)G. Badhwar (NASA-JSC), F. Cuccinotta (NASA-JSC)H. Ing, M. Smith, K. Garrow (Bubble Technology Industries)

Aircrew and Spacecrew Radiation Exposure The Dangers of Getting HighOutlineTypical Annual Radiation Exposure ImpetusAircrew Radiation Regulation Epidemiological Studies Radiation Exposure to AircrewGalactic Cosmic Ray (GCR) Exposure ConditionsSolar Magnetic Field Shielding (When)Earth Magnetic Field Shielding(Where)Atmospheric Shielding(How High)Equipment Suite DevelopmentCommercial Aircraft Measurement Aircrew Radiation StudiesAmbient Dose Equivalent Distribution (Sv)Quality FactorTEPC Data from Selected Flight RoutesData CoverageTEPC Count RateTEPC Data AnalysisLatitude Dependence:Dose Rate Vs Cutoff RigidityAltitude Effect (Balloon Flights)PCAIRE CodePCAIRE Code vs Concorde/ER-2 (NASA) (High-Altitude)Aircrew Annual ExposureCanadian Annual Occupational ExposuresHealth ImpactRadiation Exposure from Solar Particle Events (SPE)Aircrew Exposure from SPEsDose and NM Count Rate PredictionSolar Storm Effects and Solar Flare AnisotropySPE Aircrew Exposure (GLE 60)Commercial Code Development: PCAIRESysNominal In-flight Radiation EnvironmentSpace Weather Radiation EnhancementsParameters that Affect Exposure or SusceptibilitySpace Dosimetry* Radiation Exposure ComparisonsBiological Effects of Ionizing RadiationU.S. Astronaut Exposure LimitsObserved Astronaut Health Effects (Hamm & Al 2000)Summary Acknowledgements