The Gems of Masonry Emblematic and Descriptive by Sherer, John
Radiation Quantities and Units Chapter 3 Sherer. n Somatic effects n Long term somatic n Genetic...
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Transcript of Radiation Quantities and Units Chapter 3 Sherer. n Somatic effects n Long term somatic n Genetic...
Tolerance dose was replaced with Maximum Permissible dose (MPD)-dose limits-effective dose
Safe occupations (clerical) has a risk of 10 -4 per year- same as radiography
EfD – type of radiation and the sensitivity of the tissue being exposed. The Sievert is the unit of measurement
Exposure (X) Absorbed dose (D) Equivalent dose (EqD)
– Not factoring in the effect on tissue Effective dose (EfD)
– Overall risk based on absorbed dose, tissue and type of radiation
See Box 3-3 Absorbed Dose
Quality Factor, pg 63 Sherer LET pg 63 Sherer "rate in which energy is
deposited in the form of a charged particle or ion pair as it travels through matter“
Rem = RAD x QF LETS of 3% or less have a QF of 1 = same
amount of damage of rad per rem QUALITY FACTOR and weighting factor OF
ALPHA IS 20 See box Table 3-2 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?)
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 (Bushong) see Box 32-1
RADIATION INTERACTS AT ATOMIC LEVEL Atoms combine to form molecules The body is made of macromolecules What is the definition of macromolecules?