detecting radiation
DESCRIPTION
Detecting Radiation. in our Radioactive World. Nuclear Technology in our Lives. Eaten Eggs? Driven over a Metal Bridge? Attached a Postage Stamp? Use Contact Lens Solution? Used a Photocopier?. - PowerPoint PPT PresentationTRANSCRIPT
Detecting Radiation
Detecting Radiation
in our
Radioactive World
Nuclear Technology in our Lives
Eaten Eggs?
Driven over a Metal Bridge?Attached a Postage Stamp?Use Contact Lens Solution?
Used a Photocopier?
The Anticipatory Set:Which of these things is not like the other,
which of these things are kind of the same?
Detecting Radiation
What makes up glow sticks, ceramic plates, & people?
ATOMS! That’s what!
Fe
ELEMENT NAME
ATOMIC NUMBER
(# of protons)
ATOMIC
SYMBOL
ATOMIC MASS
(total # of protons & neutrons)
26 55.85
IRON
Atomic Structure of Iron
ATOMIC PARTICLES
• PROTON: within the nucleus, large mass, positive charge, identifies the element.
• NEUTRON: within the nucleus, large mass, no charge.
• electron: outside the nucleus, very small mass, negative charge.
+
RADIATION is the transmission of
energy by means of:
particles
waves
OR
• Visible Light• Microwaves• Infrared• TV – Radio Waves• Radar Waves
• High Energy UV• Radioactive Atoms• Gamma Rays• Neutrons • X-Rays
RADIATION
IonizingNon-Ionizing
Radiation with enough energy to remove an electron from its atom.
Ionizing RadiationIonizing Radiation
Ionization Radiation
Neutronsand Protons Ejected
Electron
Ionizing Radiation
Radioactivity vs. RadiationRadioactivity vs. Radiation
Alpha Particle
Neutron Particle
Beta Particle
Radioactive Atom
Gamma Ray
Characteristics
• +2 charge• 2 protons• 2 neutrons• Large mass
Alpha Particle Alpha Particle
Range
• Very short range• 1" -2" in air
Shielding
• Paper• Outer layer of skin
Hazards
• Internal
Sources
• Plutonium• Uranium• Radium• Thorium• Americium
Characteristics
• -1 charge• Small mass
Beta Particle Beta Particle
Range
• Short range• About 10' in air
Shielding
• Plastic safety glasses• Thin metal
Hazards
• Skin and eyes• Can be internal
Sources
• Radioisotopes• Activation Products• Sealed sources
Characteristics
• No charge• No mass• Similar to x-rays
Gamma Ray Gamma Ray
Range
• Long range• About 1100' in air
Hazards
• External (whole body)• Can be internal
Sources
• X-ray machines• Electron microscopes• Sealed sources• Accelerators• Nuclear reactors• Radioisotopes
Shielding
• Lead• Steel• Concrete
Paper Plastic Lead
Characteristics
• No charge• Found in nucleus
Neutron Particle Neutron Particle
Range
• Extended range
Shielding
• Water• Plastic
Hazards
• External (whole body)
Sources
• Fission• Reactor operation• Sealed sources• Accelerators
Paper Lead Water
•Radioactive atoms ON or IN an unwanted place or material.
•Nearby objects may be irradiated.
Radioactive ContaminationRadioactive Contamination
Irradiation Exposure of a material to ionizing radiation. Does NOT make the material radioactive. May cause a chemical or physical change in
the material. Possible to remove the material away from
the radioactive atoms.
Radioactive
Atoms
Radiation
=
millirem - is the basic unit of radiation dose equivalent. It measures biological risk in humans.
Abbreviation:mrem
1000 mrem = 1 rem
milliremmillirem
Terrestrial Sources
The average annual dose to the general population from natural background and man-made sources is 620 mrem.
The average annual dose to the general population from natural background and man-made sources is 620 mrem.
Cosmic Radiation
Internal Sources
Other
Radon
Radon
Average Annual DoseAverage Annual Dose
Comparison of Radiation DoseComparison of Radiation Dose
Lethal Dose
RadiationWorker Limit
ArgonneControl Limit
NaturalBackground
Average ANLRadiation Worker
GeneralEmployee Limit
Chest X-Ray
110 100 1,000 10,000 100,000 1,000,000
800,000 mrem = 800 rem
Time
Basic Protective MeasuresBasic Protective Measures
Distance
Shielding
Detecting Radiation
Geiger-Muller Tube¨
Inhalation• Breathing• Smoking
Four Ways Radioactive Material Can Enter the Body
Four Ways Radioactive Material Can Enter the Body
Wound or Cut
Absorption
Ingestion• Eating• Drinking• Chewing
Factors Affecting Biological DamageFactors Affecting Biological Damage
• Total radiation dose• Dose rate• Type of radiation• Area of body exposed• Cell sensitivity• Individual sensitivity
Biological Effects of Radiation
• Cells are undamaged.
• Cells are damaged, repair damage, & operate normally.
• Cells are damaged, repair damage, & operate abnormally
• Cells are damaged & die.
Acute Radiation DoseAcute Radiation Dose
Acute radiation dose refers to persons who receive large amounts of Radiation over a short period of time.
Chronic Radiation DoseChronic Radiation Dose
Chronic radiation dose refers to persons who receive small amounts
of radiation over a long period of time.
Health EffectsHealth Effects
Somatic Effects observed in the exposed individual
Heritable Effects observed in future generations of exposed individual