NRRPT Radiation Shielding and ALARA Principles

Question 1

What does ALARA stand for in radiation protection?

Accepted Answer

As Low As Reasonably Achievable

Answer

As Little As Radiation Allows

Answer

Authorized Limits for Absorbed Radiation Activity

Answer

Allowable Levels of Radiation Assessment

Question 2

Which shielding material is most effective for stopping gamma radiation?

Accepted Answer

Lead

Answer

Aluminum

Answer

Plastic

Answer

Wood

Question 3

The half-value layer (HVL) of a shielding material is defined as the thickness that reduces radiation intensity by what fraction?

Accepted Answer

One-half

Answer

One-quarter

Answer

One-third

Answer

Two-thirds

Question 4

Which of the three time-distance-shielding methods reduces dose by moving workers farther from a source?

Accepted Answer

Distance

Answer

Time

Answer

Shielding

Answer

Rotation

Question 5

According to the inverse square law, if you move from 1 meter to 3 meters from a point source, the dose rate becomes what fraction of the original?

Accepted Answer

1/9

Answer

1/3

Answer

1/6

Answer

1/12

Question 6

What type of radiation is best shielded by low-density materials such as plastic or water?

Accepted Answer

Neutrons

Answer

Gamma rays

Answer

Alpha particles

Answer

X-rays