what you need to know - university of...
TRANSCRIPT
RADIATIONWhat You Need To Know
UNIVERSITY OF ARKANSASOFFICE OF ENVIRONMENTAL
HEALTH AND SAFETY
Radiation . . .
IS NEITHER GOOD NOR BAD; IT ISSIMPLY A FORCE OF NATURE,LIKE GRAVITY.
Number one thing to remember about radiation …
THERE ARE TWO KINDS IONIZING
NON-IONIZING
ENERGY SPECTRUM
THE WORD “RADIATION” USUALLYREFERS TO IONIZING RADIATION
3 TYPES OF EMISSIONS• ALPHA PARTICLES• BETA PARTICLES• GAMMA RAYS
Number two thing to remember about radiation …
ALL IONIZING RADIATION IS NOT THE SAME
DIFFERENT ELEMENTAL ISOTOPESEMIT DIFFERENT TYPES OF RADIATION
STRONTIUM 90
CARBON 14
IODINE 131CESIUM 137
COBALT 60
POTASSIUM 40
URANIUM 238
PLUTONIUM 239
IonizingRadiation
• ALPHA PARTICLES• BETA PARTICLES• GAMMA RAYS
PENETRATING POWERVARIES WITH ENERGY
OF EMISSIONTYPES OF
What does this mean ?
GAMMA RAYS CAN CAUSE RADIATION BURNS
LOW ENERGY ALPHA AND BETA PARTICLES ARE NOT AS DANGEROUS
UNLESS THEY ARE INGESTED OR INHALED
Number three thing to remember about radiation…
IT IS CALLED “BACKGROUND” RADIATION AND IT COMES FROM NATURAL SOURCES
CosmicRays
CONSTANTLYBOMBARDING
THE EARTH
We are exposed to cosmic raysduring commercial airline flights.
The sun is a source of exposure to bothionizing and non-ionizing radiation.
Food and Drink
OCCURS NATURALLY IN . . .
Radiation
Is my banana radioactive ?
SORT OF, AND HERE IS WHY: BANANAS CONTAIN POTASSIUM, SOME OF IT (0.01%) IN THE FORM OF K-40, AN ABUNDANT AND NATURALLY OCCURING ISOTOPE. DON’T WORRY. BANANAS ARE PERFECTLY SAFE AND POTASSIUM IS AN ESSENTIAL ELEMENT.
EAT THEM AND ENJOY !
Rocksand
Soil
THE EARTH ITSELF
RADON IS MORE PREVALENT IN SOMEPARTS OF THE COUNTRY THAN OTHERS
Our Homes
NATURAL URANIUM RADIUM RADON GASBREAKS DOWN BREAKS DOWN
X-raysand othermedical
procedures
WE ALSO RECEIVERADIATION FROM
TobaccoSmoke
ANOTHER GOODREASON TO QUIT!
TRITIUM IN SELF-ILLUMINATING EXIT LIGHTS
VINTAGE URANIUM GLASS
Incidental Sources usually resulting in little or no significant exposure
However !THERE ARE THINGS OUT THERE THAT CAN HURT YOU !
ORPHAN SOURCES
ORPHAN SOURCES – AN ORPHAN SOURCE IS A SELF-CONTAINED RADIOACTIVESOURCE THAT IS NO LONGER UNDER PROPER REGULATORY CONTROL;
SOMETIMES FOUND IN ABANDONED FACTORIES OR IN LANDFILLS
Do Not Touch !
EXPOSURE TO
Orphan SourcesHAS CAUSED INJURY AND
DEATH !
ALCHEMISTS LONG DREAMED OFCHANGING ONE ELEMENT
INTO ANOTHER.
THEY NEVER SUCCEEDED.
RADIOACTIVE MATERIALS ACHIEVE THIS SPONTANEOUSLY.
RADIOACTIVE EMISSIONS ARE THE BYPRODUCTS OF A BREAKDOWN PROCESS.
THE BREAKDOWN PROCESS IS CALLED RADIOACTIVE “DECAY”.
THE TIME AN ELEMENT TAKES TO DECAY IS MEASURED IN HALF-LIVES.
AMERICIUM 241 NEPTUNIUM 237
Half-lifeTHE TIME IT TAKES FOR HALF THE RADIOACTIVEELEMENT TO DECAY TO ITS DAUGHTER PRODUCT
AFTER TEN HALF-LIVES, DECAY IS CONSIDERED COMPLETE
DAUGHTERS MAY ALSO BE RADIOACTIVE AND DECAY FURTHER
Different elements havedifferent half-lives.
The dosemakes
the poison.
Paracelsus1493-1541
Remember …
UNIT FOR MEASURING RADIATION DOSAGEIS THE REM
ROENTGEN EQUIVALENT IN MAN
TOTAL DOSE OF REMS DETERMINES HOW MUCH HARM A PERSON SUFFERS
OUR ANNUAL DOSE FROM ALL SOURCES IS TYPICALLY ABOUT 0.620 REM
100 + REMS• NAUSEA• VOMITING• HEADACHE• SOME LOSS OF WHITE BLOOD CELLS AND PLATELETS• VULNERABLE TO INFECTION AND HEMORRHAGE
300 + REMS • TEMPORARY HAIR LOSS• SIGNIFICANT INTERNAL HARM• DAMAGE TO NERVE CELLS• DAMAGE TO CELLS LINING THE DIGESTIVE TRACT• INCREASED CANCER RISK
450 + REMS• HALF WILL DIE• SOME SURVIVORS WILL DEVELOP CANCER LATER
800 + REMS• DEATH IN 2-14 DAYS
Radiation Sickness
Nuclear Medicine
Diagnosis
X-RAYSDISCOVERED BY ROENTGEN
BONE IS RADIO-OPAQUE
Computer Assisted Tomography
• “CAT” OR CT SCAN
• X-RAYS AND COMPUTERS CREATE IMAGES
• CAN GENERATE 3-D IMAGES IN ANY PLANE
• CAN GENERATE REALISTIC IMAGES
Diagnosis
• RADIOACTIVE LABEL ADMINISTERED• LABEL HAS SHORT HALF-LIFE• AIMED AT A SPECIFIC TARGET• OBSERVATION OF AREA OF INTEREST• MEASURMENT OF RESPONSE
Diagnostic Imaging
PATIENT MUST TAKE CARE TO PREVENTIRRADIATION OR CONTAMINATIONOF OTHERS UNTIL THE LABEL HASDECAYED AWAY.
CancerTreatment
FOCUSED BEAM RADIATIONINTENSE GAMMA RAYSKILLS TARGETED CELLS
CancerTreatment
SURGEONS MAY IMPLANTRADIOACTIVE “SEEDS”DIRECTLY INTO TUMOR
Nuclear Energy
A SAFE ALTERNATIVE TOFOSSIL FUEL ?
No easy answer . . .THE SUBJECT OF MUCH DEBATE
• ENERGY INDEPENDENCE• LOWER CARBON DIOXIDE EMISSIONS• LOWER OPERATING COSTS• LARGE GENERATING CAPACITY
• TARGET FOR TERRORISM• WASTE DISPOSAL ISSUES• HIGHER CONSTRUCTION COSTS• SAFETY CONCERNS
ProsandCons
Waste disposal is the largest unresolved issue.
How does a reactor work ?• HEAT GENERATED BY RADIOACTIVE DECAY OF FUEL RODS
• HEAT USED TO MAKE STEAM
• STEAM TURNS TURBINE
• TURBINE TURNS GENERATOR
• TRANSMISSION LINESCARRY GENERATED ELECTRICITYTO CONSUMER
Nuclear Power Accidents and ReleasesUS - THREE MILE ISLAND - 1976
• NO DEATHS OR INJURIES • PUBLIC EXPOSURE MINIMAL• LONG-TERM HEALTH EFFECTS STILL UNCLEAR
UKRAINIAN SSR - CHERNOBYL – 1986• 31 DEATHS; REACTOR STAFF AND EMERGENCY WORKERS• EXTENSIVE EXPOSURE TO BELARUS, RUSSIA AND UKRAIN• LONG-TERM HEALTH EFFECTS LIKELY TO BE EXTENSIVE
JAPAN - FUKISHIMA /DAIICHI – 2011• NO DEATHS AT THIS TIME DUE TO REACTOR• LONG-TERM HEALTH EFFECTS UNKNOWN
Safety Concerns . . .
Put into Perspective . . .FROM 2000 - 2009
• 317 – COAL MINE DEATHS IN US
• 51,267 – COAL MINE DEATHS IN CHINA
• MANY MORE WILL DIE FROM BLACK LUNG
FROM 2000 – 2009
• 161 OIL AND GAS FIELD DEATHS IN USA ALONE
• UNTOLD DAMAGE TO THE ENVIRONMENT
Deep Water Horizon - 2010• 11 MEN DIED
• MARINE AND COASTALENVIRONMENTAL DISASTER
BANQIAO HYDROELECTRIC DAM FAILURE - 1975
• ESTIMATES OF DEATHS RANGE FROM 171,000 TO 235,000• 11,000,000 PEOPLE DISPLACED BY THE FLOOD• PRECEDED BY FAILURE OF SHIMANTAN RESERVOIR DAM UPSTREAM• RESULTED IN THE FAILURE OF 60 MORE DAMS IN CHINA’S HENAN PROVINCE
COAL – 278 CHINACOAL – 15 USA OIL – 36 (36% OF WORLD ENERGY) NATURAL GAS – 4 (21% OF WORLD ENERGY) BIOFUEL/BIOMASS – 12 PEAT – 12 SOLAR (ROOFTOP) – 0.44 (LESS THAN 0.1% OF WORLD ENERGY) WIND – 0.15 (LESS THAN 1% OF WORLD ENERGY) HYDRO – 0.10 (EUROPE DEATH RATE, 2.2% OF WORLD ENERGY)HYDRO – 1.4 (WORLD INCLUDING 171,000 DEAD IN BANQIAO )NUCLEAR – 0.04 (5.9% OF WORLD ENERGY)
Deaths Per Terawatt-hour (TWH) Of ElectricityGenerated From All Energy Sources
1 TWH = 1MILLION MILLION WATTS ACTING FOR ONE HOUR
Calculating the Cost in Human Lives
Energy has its costs . . .
. . . no matter the source.
Radiation gives us valuable tools.
Handle them with care !
SUMMARY
The Good…
The Bad …
The Ugly…
The Unthinkable
THE END(REALLY)