Dosimetry and Exposure Control Flashcards
7 cards from real NRRPT practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Dosimetry and Exposure Control flashcards as text
A worker's quarterly TEDE is calculated by summing the deep dose equivalent (DDE) and the committed effective dose equivalent (CEDE). If DDE = 300 mrem and CEDE = 120 mrem, what is the TEDE?
Answer: 420 mrem
TEDE = DDE + CEDE = 300 mrem + 120 mrem = 420 mrem.
The Annual Limit on Intake (ALI) for a radionuclide is defined as the intake that would result in a committed effective dose equivalent of:
Answer: 5 rem (0.05 Sv)
The ALI is the intake of a radionuclide in a year that would result in a committed effective dose equivalent of 5 rem (0.05 Sv), the annual occupational limit.
In whole-body counting, which detection method is most commonly used to measure gamma-emitting internal contamination in a worker?
Answer: NaI(Tl) or HPGe scintillation/semiconductor detector system
Whole-body counters use large NaI(Tl) scintillators or HPGe detectors to directly measure gamma photons emitted from internal radionuclides.
Under the 10 CFR Part 20 dose constraint concept for air emissions, licensees must constrain doses to individual members of the public to what level?
Answer: 10 mrem/yr
10 CFR 20.1101(d) requires licensees to constrain airborne radioactive emissions so that doses to individual members of the public do not exceed 10 mrem/yr.
Which administrative control sets dose limits lower than regulatory limits to ensure workers don't inadvertently exceed legal limits?
Answer: Administrative control level (ACL)
Administrative control levels (ACLs) are internal organizational limits set below regulatory limits to provide a safety margin and trigger corrective action before limits are exceeded.
A Derived Air Concentration (DAC) for an inhalation pathway is defined as the airborne concentration that, if breathed for:
Answer: 2000 hours per year at work rate breathing, results in intake of 1 ALI
DAC is the airborne concentration of a radionuclide that, if inhaled for a full work year (2000 hours) at light work breathing rate, would result in intake of 1 ALI.
Which of the following best describes the purpose of a nuclear track etch dosimeter (e.g., CR-39)?
Answer: Measuring fast neutron doses through recoil proton tracks in plastic
CR-39 track etch dosimeters measure fast neutron doses by detecting the tracks left by recoil protons produced when neutrons interact with hydrogen atoms in the plastic.