BASIC CONCEPTS

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BASIC CONCEPTS

• How much do you already know?

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????QUESTIONS???

• MATTER
• Occupies_____________
• is a material substance
• Has________and shape
• Building blocks of matter are_______and
  __________.

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????QUESTIONS???

• MATTER
• The primary characteristic of matter is
  _____________
• Mass is the quantity or quality of an object?
• ANSWERQUANTITY
• Does mass change when matter changes?
• Give an example of a change of matter.

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????QUESTIONS???

• WEIGHT
• is the mass of matter in an object in ?
• Why do we weigh less on the moon
• than on earth?

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Types of energy (joules or eV)

• Potential
• Kinetic
• Chemical
• Electrical
• Thermal
• Nuclear
• Electromagnetic

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RADIATION

• ENERGY EMITTED AND TRANSFERRED THROUGH SPACE
• PIANO STRINGRADIATE SOUND
• RIPPLES OR WAVESWAVES RADIATE

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IONIZING RADIATION(AGAIN!!!)

• Removes orbital electron from atom
• this electron can disrupt surrounding atoms by
  transferring energy to them.
• This renegade(free) electron- negative ion
• The atom that lost the electron- positive ion
• negative ion positive ion ion pair

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What two forms of electromagnetic radiation
ionize matter?

• X-rays
• Gamma rays

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What two particulate forms of radiation ionize
matter?

• alpha
• beta

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SOURCES OF RADIATION HARMFUL TO HUMANS

• Natural
• Cosmic
• Terrestrial
• Naturally occurring radionucleides in the human
  body

• Manmade
• medical x-rays
• nuclear power plants
• industrial sources
• watch dials
• smoke detectors
• TV
• Airport surveillance systems

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DID YOU KNOW?

• Naturally man-made radiation occurring
  radiation contributes 360 mrads to the average
  absorbed dose to humans.
• Diagnostic x-rays make up the largest source of
  man-made radiation (39 mrem per year-50 mrem per
  year)

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IN THE EARLY YEARS OF USING X-RAYS

• Skin damage (erythema)
• loss of hair (alopecia)
• low red blood cell counts(anemia)
• INJURIES DUE TO
• low energy radiation
• looooonnnngggg exposure times
• (30 minutes!!!!!!!!!!!!!!!)

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REDUCTION TO RADIATION EXPOSURE

• Coolidge tube (Hot-cathode x-ray tube)
• vacuum tube
• intensity and energy to be selected (1913)
• Snook transformer
• High voltage power, induction coils (1910)
• Potter-bucky grid (1921)

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PROTECTIVE APPAREL WAS DEVELOPED WHEN IT WAS
NOTED THAT RADIOLOGISTS WERE DEVELOPING AT A HIGH
RATE OF LEUKEMIA AND APLASTIC ANEMIA
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Effects of radiation

• Early
• blood changes
• decreased sperm count

• Latent
• cancer changes
• possible genetic effects

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REGULATION HISTORY

• 1966- ICRP developed
• ALARA
• Radiation must have a benefit
• Dose should not exceed limits for
  specific
  circumstances

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REGULATION HISTORY

• 1987- NCRP established
• limits for radiation exposures for
  radiation workers and non-radiation
  workers
• limits were to minimize potential
  harm

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CARDINAL PRINCIPLES OF RADIATION PROTECTION

• T
• D
• S

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DEVICES FOR MINIMIZING RADIATION TO PT/WORKER

• Filtration
• collimation
• Intensifying screen
• Protective barriers
• Protective apparel
• Technical factors (Highest optimal kVp, shortest
  time)

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The risk of radiation exposure in diagnostic
imaging departments is minimal. Radiography is
now considered a radiation safe
occupation.RADIOLOGIC SCIENCE FOR
TECHNOLOGISTS,Stewart Bushong, 1997Page 7