CRI Radiation Safety & Protection 5

Question 1

What is the inverse square law relationship between distance and radiation intensity?

Accepted Answer

Intensity decreases with the square of distance

Answer

The inverse square law states that radiation intensity is inversely proportional to the square of the distance from a point source.

Question 2

A survey meter reads 40 mR/hr at 5 feet from a source. Using the inverse square law, what is the approximate dose rate at 10 feet?

Accepted Answer

10 mR/hr

Answer

Doubling the distance reduces intensity by a factor of 4 (2²), so 40 mR/hr ÷ 4 = 10 mR/hr.

Question 3

What is the primary biological effect of concern from low-level, chronic radiation exposure to workers?

Accepted Answer

Stochastic effects such as cancer induction

Answer

Stochastic effects like cancer induction are the primary concern for chronic low-level occupational exposure, with no threshold dose.

Question 4

Which document must accompany a sealed radioactive source during transport by a radiographer?

Accepted Answer

Shipping paper with proper UN number and description

Answer

DOT regulations require shipping papers identifying the radioactive material, UN number, quantity, and hazard class during transport.

Question 5

What condition defines a 'High Radiation Area' under NRC regulations?

Accepted Answer

Dose rate exceeds 1 mSv/hr at 30 cm

Answer

A High Radiation Area is defined as any area where dose rates can exceed 1 mSv/hr (100 mrem/hr) at 30 cm from the source or surface.

(CRI) Certified Radiographic Interpreter Practice Test