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IONIZING RADIATION (PowerPoint download)

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					IONIZING RADIATION




                     1
     Non-Ionizing Radiation
Does not have enough energy to remove
  electrons from surrounding atoms




                                        2
There Are Lots Of Types Of Radiation




                                       3
Atomic Structure
 All matter is made up of atoms
   Protons
   Neutrons
   Electrons




 Not all atoms are stable
 Unstable atoms are known as radioactive
  atoms
                                            4
        Our 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
                                                  5
6
Unstable Atoms Emit Radiation




                                7
                    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.


        4
        2   He
                                     8
Alpha Radiation is only a hazard when inside
your body (internal hazard)



         can’t Your skin will stop it
               penetrate skin
                                         internal hazard

                                        stopped by paper


                                found in soil,
                                radon and other
                                radioactive
                                materials
                                                           9
Beta Particle
        The beta particle is a high
        energy electron. It has a
        charge of negative one. It
        has the following symbol.


                    -




                                      10
Beta Radiation is a Skin, Eye and Internal
Hazard




             skin, eye and internal hazard



           stopped by plastic

                      found in natural food, air and water


                                                         11
               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.



           
                                 12
X and gamma radiation are penetrating
radiation and an EXTERNAL HAZARD.




    stopped by lead            found in
                               medical uses




   naturally present in soil
   and cosmic radiation
                                              13
Background and Manufactured Radiation
       In the U.S. Contributes
         360 mrem per Year

                         radon - 200


cosmic - 28




  diet - 40


                             terrestrial - 28
                                                14
                Uses of Radiation




Nuclear Power            Food sterilization

                                              Industrial and
                                              Medical Uses



     Consumer products                                         15
 Manufactured sources of radiation
 contribute an average of 60 mrem/year

cigarette smoking - 1300 mrem


                                      round trip US by air
           medical - 53 mrem             5 mrem per trip



      building materials - 3.6 mrem

     smoke detectors - 0.0001 mrem

      fallout < 1 mrem
                                                        16
         Radiation Versus Radioactive
                Contamination

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



 RadioactiveContamination is radioactive
 material usually in any location you do not
 want it.

                                               17
 Biological Effects of Radiation


 Earlyscientists determined that
 radiation was a useful tool but it
 could hurt you.

 Radiation can cause burns and
 cellular damage.



                                      18
Biological Effects of Radiation

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




                                                       19
SIGNS ARE REQUIRED TO NOTIFY EVERYONE OF
       THE PRESENCE OF RADIATION




                                       20
  MONITORING RADIATION
        EXPOSURE

Radiation dosimeters measures radiation
 dose to people.




                                          21
    Minimize Dose By Good
          Practices

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




                                   22
 Radiation is detected with survey meters


                     Beta, Gamma & X-ray
Alpha Survey Meter
                     Survey Meter




                                            23

				
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posted:3/7/2012
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