NRRPT Radiological Control & Safety Procedures 2 — Questions and Answers
Question 1: What is the primary purpose of a Radiological Work Permit (RWP)?
- To document radiation dose received by workers
- To authorize and control work in radiologically controlled areas (Correct answer)
- To record instrument calibration data
- To notify regulators of planned work
Correct answer: To authorize and control work in radiologically controlled areas
An RWP authorizes specific work in radiologically controlled areas and specifies controls, dose limits, and protective measures required.
Question 2: During a radiological survey, a technician detects a contamination level of 10,000 dpm/100 cm² beta on an unrestricted surface. What is the appropriate immediate action?
- Continue work and note in the survey record
- Post the area and restrict access pending decontamination (Correct answer)
- Increase ventilation and proceed with caution
- Notify the NRC immediately
Correct answer: Post the area and restrict access pending decontamination
Contamination exceeding release limits on unrestricted surfaces requires immediate area posting and restriction until decontamination reduces levels to acceptable limits.
Question 3: Which respiratory protection device provides the highest protection factor in a radiological environment?
- Half-face air-purifying respirator
- Full-face air-purifying respirator
- Powered air-purifying respirator (PAPR)
- Self-contained breathing apparatus (SCBA) (Correct answer)
Correct answer: Self-contained breathing apparatus (SCBA)
SCBA provides a protection factor of 10,000, the highest available, because it supplies breathing air independent of the surrounding atmosphere.
Question 4: What is 'ALARA' and which regulatory framework mandates its application?
- As Low As Reasonably Achievable; mandated by 10 CFR 20 (Correct answer)
- As Low As Readily Available; mandated by 29 CFR 1910
- As Low As Reasonably Achievable; mandated by 40 CFR 61
- As Low As Radiologically Acceptable; mandated by 10 CFR 50
Correct answer: As Low As Reasonably Achievable; mandated by 10 CFR 20
ALARA stands for As Low As Reasonably Achievable and is required under 10 CFR 20.1101 for all NRC licensees to keep radiation exposures as low as practicable.
Question 5: A radiation protection technician must verify that a radiation-generating device is de-energized before allowing entry. Which verification method is most reliable?
- Checking the control panel indicator lights
- Verifying the interlock system is engaged
- Using a calibrated survey meter to confirm no radiation field is present (Correct answer)
- Reviewing the maintenance log for shutdown confirmation
Correct answer: Using a calibrated survey meter to confirm no radiation field is present
Direct measurement with a calibrated survey meter provides the most reliable confirmation that a radiation-generating device is not producing radiation.
Question 6: Which of the following best describes the function of a dosimeter alarming at its set point during radiological work?
- Indicates the worker has received a lethal dose
- Alerts the worker that a pre-set dose or dose rate threshold has been reached (Correct answer)
- Signals that the dosimeter battery is low
- Confirms that background radiation levels are normal
Correct answer: Alerts the worker that a pre-set dose or dose rate threshold has been reached
Electronic personal dosimeters alarm at pre-set dose or dose rate thresholds to warn workers before they exceed planned exposure limits.
Question 7: Under 10 CFR 20, what is the occupational whole-body dose limit per year for a radiation worker?
- 1 rem (0.01 Sv)
- 5 rem (0.05 Sv) (Correct answer)
- 10 rem (0.1 Sv)
- 15 rem (0.15 Sv)
Correct answer: 5 rem (0.05 Sv)
10 CFR 20.1201 sets the occupational total effective dose equivalent (TEDE) limit at 5 rem (0.05 Sv) per year.
NRRPT Radiological Control & Safety Procedures 2
What is the primary purpose of a Radiological Work Permit (RWP)?