RSO Radiation Biology and Health Effects 3

Question 1

The ALARA principle in radiation protection stands for:

Accepted Answer

As Low As Reasonably Achievable

Answer

ALARA stands for 'As Low As Reasonably Achievable,' requiring that radiation doses be kept as low as reasonably achievable, taking into account social and economic factors.

Question 2

Indirect action in radiation biology refers to:

Accepted Answer

Radiation ionizing water to produce free radicals that damage DNA

Answer

Indirect action involves radiation ionizing water molecules in cells to produce hydroxyl radicals and other reactive species that then diffuse to and damage DNA.

Question 3

Which cell type is among the MOST radiosensitive according to the Law of Bergonié and Tribondeau?

Accepted Answer

Lymphocytes

Answer

Lymphocytes are highly radiosensitive despite being non-dividing; they are an exception to Bergonié and Tribondeau's rule and die via apoptosis at very low doses.

Question 4

The mean lethal dose (LD50/30) for humans from acute whole-body radiation exposure without medical treatment is approximately:

Accepted Answer

4–5 Gy

Answer

The LD50/30 for humans without medical support is approximately 3–5 Gy delivered acutely; supportive care can raise this to 6–7 Gy.

Question 5

An RSO reviewing dosimetry data notices that an embryo/fetus has received 4 mSv during the declared pregnancy. NRC regulations limit fetal dose during the entire gestation period to:

Accepted Answer

5 mSv

Answer

NRC regulations (10 CFR 20.1208) limit the dose to an embryo/fetus during the entire gestation period to 5 mSv (500 mrem) once the pregnancy is declared.

RSO - Radiation Safety Officer Practice Test

RSO - Radiation Safety Officer Practice Test

RSO Radiation Biology and Health Effects 3