Radiation Quantities and Units Chapter 3 Sherer Chapter 33 Bushong

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

 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

      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

WHICH HAS A HIGHER LET NUMBER?

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

Radiation Induced Responses  NON-STOCHASTIC AKA (DETERMINISTIC)  STOCHASTIC AKA PROBABILISTIC

What do they mean?

  Exposure (X) Absorbed dose (D)   What strikes the body Deposit of energy in body  Equivalent dose (EqD)  Effective dose (EfD)   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

 W R associated with Equivalent Dose- table 3-2  W T associated with Effective Dose- table 3-3

Radiobiology and Cellular Biology (Bushong Chapter 33)

When an atom is ionized  Chemical binding properties change  in large molecules: breakage or relocation of molecules…become abnormal  Abnormal means  Function improperly  cease to function -impairment or death of cell

Damage is Reversible  Ionized atoms become neutral…How?

 Molecules are mended by repair enzymes  Immediate response to radiation  Latent response  Pg 484 (Bushong) see Box 33-1

RADIATION INTERACTS AT ATOMIC LEVEL  Atoms combine to form molecules  The body is made of macromolecules  What is the definition of macromolecules?

With this kind of potential damage….

The government tends to get involved CHAPTER 7 SHERER

YOU ARE RESPONSIBLE FOR DIFFERENTIATING BETWEEN  ICRP  NCRP  UNSCEAR  NAS/NRC-BEIR  NRC  EPA  FDA  OSHA

DEFINE  RSC  RSO  NCRP REPORT NO 116