Mosby Ch. 5 - Radiation Protection & Safety Flashcards
exposure is measured using?
roentgen
coulomb/kilogram
absorbed dose is measured using?
rad
gray
equivalent dose is measured using?
rem
sievert
the term quality factor (Q):
a. varies with different types of radation
b. varies with different types of tissue
c. varies as a function of age and gender
d. is measured in rem
a. varies with different types of radation
radiation with high LET have higher quality factors or radiation weighting factors
the fraction of time that a radiation beam is directed at a specific barrier is termed the ___________.
use factor
T/F: the requirement for barrier protection in walls/ceiling from primary radiation is reduce when there is a beam stopper on the treatment unit
true
the largest dose from natural background radiaiton comes from
a. terrestrial
b. radon
c. cosmic
d. internal
b. radon
long forceps are required for direct handling of radioactive sources so that:
a. exposure time to the handler’s hands is decreased
b. exposure time to the handler’s hands is increased
c. amount of exposure to handler’s hands is decreased
d. amount of exposure to handler’s hands is increased
c. amount of exposure to handler’s hands is decreased
the use of long forceps allows the handler to take advantage of the inverse square principle. increasing the distance decreases the dose
the radioactie source inventory room should have a sign that reads:
a. caution radioactive material
b. caution radiation area
c. caution high radiaiton area
d. grave danger-high radiation area
a. caution radioactive material
in the construction of a new radiaiton therapy center, the choices for primary barriers include concrete, lead, or iron. Measure for measure, i would need more ______ for adequate absorption.
a. concrete
b. lead
c. iron
a. concrete
concrete is less dense than lead or iron and therefore would have a lower attenuation coeffecient requiring more material for addequate limitation of exposure
the half value layer for a 6 MV beam is 22 mm of lead. it’s linear attenuation coefficient is:
a. 31.7 mm-1
b. 0.0315 mm-1
c. 0.693 mm-1
d. 15.24 mm-1
b. 0.0315 mm-1
22 = 0.693/μ
22 μ = 0.693
a monthly radaiiton exposure report says an employee received 0.5 Sv. if the source of exposure were determined to be gamma radiaiton, the tranlation to absorbed dose would be:
a. 0.5 Sv = 0.5 Gy
b. 0.5 Sv= 0.5 cGy
c. 0.5 Sv = 10 Gy
d. 0.5 Sv = 100 Gy
a. 0.5 Sv = 0.5 Gy
Sv = Gray x Quality factor
quality factor for gamma rays is 1
0.5 Sv = x (1)
quality factor for x ray
1
quality factor for gama rays
1
quality factor for electrons
1
