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IONIZING RADIATION

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Non-Ionizing RadiationDoes not have enough energy to

remove electrons from surrounding atoms

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There Are Lots Of Types Of Radiation

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Atomic Structure All matter is made up of atoms

Protons Neutrons Electrons

Not all atoms are stable Unstable atoms are known as radioactive

atoms

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Our Bodies Are ResilientOur Bodies Are Resilient

_ DNA damage is most important and can lead to cell malfunction or death.

_ Our body has ~ 60 trillion cells

» Each cell takes “a hit” about every 10 seconds, resulting in tens of millions of DNA breaks per cell each year.

» BACKGROUND RADIATION causes only a very small fraction of these breaks (~ 5 DNA breaks per cell each year).

_ Our bodies have a highly efficient DNA repair mechanisms

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Unstable Atoms Emit Radiation

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Alpha Particle

An alpha particle contains two protons and two neutrons. An alpha particle is essentially the nucleus of a helium nucleus (but with a great deal more energy). It has a charge of positive two. It is represented by the following chemical symbol.

He4

2

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Alpha Radiation is only a hazard when inside your body (internal hazard)

Your skin will stop itcan’t penetrate skininternal hazard

stopped by paper

found in soil, radon and other radioactive materials

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Beta Particle

The beta particle is a high energy electron. It has a charge of negative one. It has the following symbol.

-

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Beta Radiation is a Skin, Eye and Internal Hazard

skin, eye and internal hazard

stopped by plastic

found in natural food, air and water

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Gamma Radiation

Gamma rays (and Xrays and Cosmic rays ) are electromagnetic radiation. They are pure energy with no no charge or mass. The gamma ray has the following symbol.

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stopped by lead

naturally present in soil and cosmic radiation

found in medical uses

X and gamma radiation are penetrating radiation and an EXTERNAL HAZARD.

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Background and Manufactured Radiation In the U.S. Contributes

360 mrem per Year

cosmic - 28

diet - 40

terrestrial - 28

radon - 200

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Uses of Radiation

Food sterilizationNuclear Power

Consumer products

Industrial and Industrial and Medical UsesMedical Uses

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mrem

Manufactured sources of radiation contribute an average of 60 mrem/year

cigarette smoking - 1300 mrem

round trip US by air

5 mrem per trip

building materials - 3.6

fallout < 1

smoke detectors - 0.0001

medical - 53

mrem

mrem

mrem

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Radiation Versus Radioactive Contamination

Radiation is particles or waves of energy emitted from unstable atoms.

Radioactive Contamination is radioactive material usually in any location you do not want it.

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Biological Effects of Radiation

Early scientists determined that radiation was a useful tool but it could hurt you.

Radiation can cause burns and cellular damage.

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Biological Effects of Radiation

The principle hazard from radiation exposure is an increase in the risk of cancer induction.

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SIGNS ARE REQUIRED TO NOTIFY EVERYONE OF THE PRESENCE OF RADIATION

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MONITORING RADIATION EXPOSURE

Radiation dosimeters measures radiation dose to people.

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Minimize Dose By Good Practices

TIME - reduce time of exposure DISTANCE - increase distance SHIELDING - use shielding

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OFF

BATT

x10K

x1Kx100

x10

RESET

AUDIO

ON

0

2040 60

80

100

BAT.COUNTS/MI

NGENERAL ELECTRIC

GE

ALPHA SURVEY METER LEA75-1854 SER.NO.

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Alpha Survey Meter

Radiation is detected with survey meters

Beta, Gamma & X-ray Survey Meter