NRRPT - National Registry of Radiation Protection Technicians Dosimetry and Exposure Control Questions and Answers

Question 1

A radiation worker needs to perform a task in a high radiation area with a dose rate of 150 mrem/hr.
The administrative dose limit for this task is 100 mrem.
What is the maximum stay time permitted for the worker to complete the task without exceeding the administrative limit?

Accepted Answer

40 minutes

Answer

20 minutes

Answer

30 minutes

Answer

60 minutes

Question 2

Which of the following personal dosimeters uses a crystalline solid that, when heated after exposure to ionizing radiation, emits light proportional to the dose received?

Accepted Answer

Thermoluminescent Dosimeter (TLD)

Answer

Film Badge

Answer

Pocket Ionization Chamber

Answer

Optically Stimulated Luminescence (OSL) Dosimeter

Question 3

A technician measures a dose rate of 400 mR/hr at a distance of 2 feet from a point source. If the technician moves to a distance of 8 feet from the source, what will the new dose rate be, according to the inverse square law?

Accepted Answer

25 mR/hr

Answer

100 mR/hr

Answer

50 mR/hr

Answer

12.5 mR/hr

Question 4

The fundamental principle of ALARA (As Low As Reasonably Achievable) in radiation protection means that:

Accepted Answer

Radiation exposures should be maintained as far below the dose limits as is practical, taking into account social and economic factors.

Answer

All radiation exposure must be eliminated completely.

Answer

Exposures must be kept below the annual regulatory limits, with no other considerations.

Answer

Only acute, high-level exposures need to be managed and controlled.

Question 5

What is the primary operational difference between an Optically Stimulated Luminescence (OSL) dosimeter and a Thermoluminescent Dosimeter (TLD)?

Accepted Answer

OSL dosimeters can be re-read multiple times, while the signal from a TLD is typically erased upon reading.

Answer

OSL dosimeters are stimulated with heat, while TLDs are stimulated with light.

Answer

TLDs are more sensitive to low doses of radiation than OSL dosimeters.

Answer

OSL dosimeters measure dose in real-time, whereas TLDs provide an integrated dose over time.

Question 6

An administrative control level is established by a licensee for radiation workers. What is the primary purpose of this level in an exposure control program?

Accepted Answer

To serve as a threshold that, if reached, triggers an investigation or requires specific authorization for further exposure.

Answer

To replace the federal regulatory dose limits with a less strict standard.

Answer

To define the absolute maximum dose a worker can legally receive in one year.

Answer

To measure the average background radiation in a specific work area.