Radiation Biology and Health Effects Flashcards
6 cards from real RSO practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Radiation Biology and Health Effects flashcards as text
The term 'effective dose' accounts for which two factors beyond absorbed dose?
Answer: Radiation weighting factor and tissue weighting factor
Effective dose is calculated by multiplying absorbed dose by a radiation weighting factor (for radiation type) and then by tissue weighting factors (for organ sensitivity) to give a single risk estimate.
Which of the following is a deterministic radiation effect?
Answer: Cataract of the eye lens
Cataracts are a deterministic effect with a threshold dose, meaning they only occur above a certain dose level, and severity increases with dose above that threshold.
In radiobiology, the 'four Rs' of radiobiology include repair, reoxygenation, redistribution, and:
Answer: Repopulation
The four Rs of radiobiology are repair of sublethal damage, reoxygenation of hypoxic cells, redistribution of cells through the cell cycle, and repopulation of surviving cells.
The tissue weighting factor (wT) for the gonads in ICRP Publication 103 is:
Answer: 0.08
ICRP Publication 103 assigns gonads a tissue weighting factor of 0.08, reflecting their contribution to total detriment-adjusted risk from uniform whole-body irradiation.
Which radiation-induced DNA lesion is considered the most biologically significant for cell killing and carcinogenesis?
Answer: Double-strand break
Double-strand breaks (DSBs) are the most critical DNA lesions because both strands are severed, making faithful repair difficult and increasing the risk of chromosomal aberrations.
A radiation worker receives an equivalent dose of 50 mSv to the lens of the eye in one year. According to current ICRP guidance, this:
Answer: Exceeds the annual occupational lens dose limit of 20 mSv
The current ICRP and NRC occupational lens dose limit is 20 mSv/year (averaged over 5 years, with no single year exceeding 50 mSv), and 50 mSv in one year approaches or exceeds this limit depending on the averaging approach.