Radiation Quantities and Units

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Radiation Quantities and Units

• Chapter 3
• Sherer
• Chapter 33 Bushong

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• Somatic effects
• Long term somatic
• Genetic effects
• Box 3-1

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• Quality Factor, pg 56 Sherer
• "rate in which energy is deposited in the form of
  a charged particle or ion pair as it travels
  through matter"
• LET pg 57 Sherer
• Radiographic isotopes pg 46 Bushong
• ionization pg. 5 Bushong
• Natural sources of radiation, pg 5 Bushong

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• QUALITY FACTOR (QF)
• measure of biologic impact or damage of a
  particular type of radiation
• Rem RAD x QF
• LETS of 3 or less have a QF of 1 same amount
  of damage of rad per rem
• QUALITY FACTOR OF ALPHA IS 20 See box Table 3-1
  Sherer
• 1 RAD 20 REM FOR ALPHA PARTICLE ABSORPTION

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WHICH HAS A HIGHER LET NUMBER?

• X-rays (HIGH OR LOW?)
• Alpha (HIGH OR LOW?)
• Beta (HIGH OR LOW?)
• Gamma (HIGH OR LOW?)

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Radiation Induced Responses

• NON-STOCHASTIC AKA (DETERMINISTIC)
• STOCHASTIC AKA PROBABILISTIC

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What do they mean?

• Exposure (X)
• Absorbed dose (D)
• Equivalent dose (EqD)
• Effective dose (EfD)

• What strikes the body
• Deposit of energy in body
• Calculated based on absorbed dose and associated
  radiation weighting factor (type/energy of a
  specific radiation)
• More tissues radiosensitive than others (tissue
  weighting factor see Table 3-3

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• WR associated with Equivalent Dose- table 3-2
• WT associated with Effective Dose- table 3-3

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Radiobiology and Cellular Biology (Bushong
Chapter 33)
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When an atom is ionized

• Chemical binding properties change
• in large molecules breakage or relocation of
  moleculesbecome abnormal
• Abnormal means
• Function improperly
• cease to function -impairment or death of cell

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Damage is Reversible

• Ionized atoms become neutralHow?
• Molecules are mended by repair enzymes
• Immediate response to radiation
• Latent response
• Pg 484 (Bushong) see Box 33-1

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RADIATION INTERACTS AT ATOMIC LEVEL

• Atoms combine to form molecules
• The body is made of macromolecules
• What is the definition of macromolecules?

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With this kind of potential damage.

• The government tends to get involved
• CHAPTER 7 SHERER

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YOU ARE RESPONSIBLE FOR DIFFERENTIATING BETWEEN

• ICRP
• NCRP
• UNSCEAR
• NAS/NRC-BEIR
• NRC
• EPA
• FDA
• OSHA

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DEFINE

• RSC
• RSO
• NCRP REPORT NO 116