Exposure and Dose Flashcards
What ultimately gives the dose from radiation?
Secondary electrons from the ionizations caused by radiation
Exposure (X-Unit)
Quantity of photon radiation that produces 1C/kg in air
Roentgen
The amount of photon radiation that produces 1 ESU of charge in 1 cm^3 of air at STP
1 R = ? X-units
2.58E(-4) X-units
Absorbed Dose
The mean energy imparted by ionizing radiation to matter
Absorbed dose units and base units
1 Gy = 1 J/kg
1 Rad = 100 erg/g
1 R = ? Rad
0.88 Rad
KERMA
Sum of the initial kinetic energy released per unit mass produced by uncharged ionizing radiation
Difference between KERMA and absorbed dose
Kerma is the initial KE created in the volume and absorbed dose is the kinetic energy that stays in the volume
Dose Equivalent or Equivalent Dose
DE = SUM [ (Radiation Weighting Factor) * (Absorbed Dose) ]
Effective Dose Equivalent or Effective Dose
EDE = SUM [ (Tissue Weighting Factor) * (Dose Equivalent) ]
Committed Dose Equivalent
Dose equivalent to organs or tissues that will be received by an intake of radioactive material over 50 years following the intake
Committed Effective Dose Equivalent
CEDE = SUM [ (Tissue Weighting Factor) * (CDE) ]
Total Effective Dose Equivalent
TEDE = EDE (external) + CEDE (internal)
Defined depths in tissue for Deep dose equivalent, Shallow dose equivalent, and Lens dose equivalent
DDE = 1 cm (1000 mg/cm^2)
SDE = 0.007 cm (7 mg/cm^2)
LDE = 0.3 cm (300 mg/cm^2)
