NMTCB Radiation Safety Final Exam
Actual Exam 2026/2027 Prep Questions
Complete Accurate Exam Approved
Questions And Correct Verified Solutions
With Detailed Rationales (100% Correct
Verified Answers)
1. What is the NRC annual occupational dose limit for the total effective dose equivalent
(TEDE) to the whole body?
A) 0.5 rem (5 mSv)
B) 5 rem (50 mSv)
C) 50 rem (500 mSv)
D) 100 rem (1 Sv)
Answer: B) 5 rem (50 mSv)
Rationale: 10 CFR 20.1201 establishes 5 rem (50 mSv) TEDE as the annual occupational limit for
whole body exposure.
2. The annual dose limit for the lens of the eye for an occupational worker under NRC
regulations is:
A) 5 rem (50 mSv)
B) 15 rem (150 mSv)
C) 50 rem (500 mSv)
D) 1 rem (10 mSv)
Answer: B) 15 rem (150 mSv)
Rationale: NRC sets the lens of the eye limit at 15 rem/year. Note: ICRP recommends 2 rem (20
mSv)/year, but NRC has not adopted this change.
3. The shallow dose equivalent (SDE) is used to monitor dose to:
A) The whole body
B) The lens of the eye
,C) The skin and extremities
D) Deep organs
Answer: C) The skin and extremities
Rationale: SDE measures dose at a depth of 0.007 cm (7 mg/cm²), typically assessed with ring
dosimeters.
4. The dose limit for a declared pregnant radiation worker (fetus) is:
A) 0.5 mSv per month
B) 5 mSv (0.5 rem) total for the gestation period
C) 50 mSv (5 rem) total for the gestation period
D) 1 mSv per week
Answer: B) 5 mSv (0.5 rem) total for the gestation period
Rationale: NRC requires that the fetal dose not exceed 5 mSv (0.5 rem) for the entire gestation
period.
5. What is the annual occupational dose limit for the skin or any extremity?
A) 5 rem (50 mSv)
B) 15 rem (150 mSv)
C) 50 rem (500 mSv)
D) 100 rem (1 Sv)
Answer: C) 50 rem (500 mSv)
Rationale: Extremity dose limit is 50 rem/year.
6. The annual dose limit for a member of the general public (continuous exposure) is:
A) 0.1 rem (1 mSv)
B) 0.5 rem (5 mSv)
C) 5 rem (50 mSv)
D) 1 rem (10 mSv)
Answer: A) 0.1 rem (1 mSv)
Rationale: Public dose limits are significantly lower than occupational limits.
7. The committed effective dose equivalent (CEDE) refers to:
A) Dose from a single external exposure event
B) Dose integrated over 50 years for adults after intake of radionuclides
C) Dose to the skin only
D) Dose to the fetus only
,Answer: B) Dose integrated over 50 years for adults after intake of radionuclides
Rationale: CEDE accounts for the total stochastic risk from internally deposited radionuclides
over the integration period.
8. The deep dose equivalent (DDE) is measured at what depth in tissue?
A) 0.007 cm
B) 0.3 cm
C) 1 cm
D) 5 cm
Answer: C) 1 cm
Rationale: DDE corresponds to dose at 1 cm depth, representing whole-body exposure from
penetrating radiation.
9. Which dosimeter type uses thermally stimulated luminescence to record dose?
A) Film badge
B) TLD (Thermoluminescent dosimeter)
C) OSL (Optically stimulated luminescence) badge
D) Electronic personal dosimeter
Answer: B) TLD
Rationale: TLDs store energy in crystal lattice defects and release light when heated
proportional to absorbed dose.
10. 1 mSv equals how many mrem?
A) 10 mrem
B) 100 mrem
C) 1000 mrem
D) 0.1 mrem
Answer: B) 100 mrem
Rationale: Conversion factor: 1 Sv = 100 rem; therefore 1 mSv = 100 mrem.
11. The committed dose equivalent (CDE) for an organ is calculated by:
A) Multiplying the absorbed dose by a tissue weighting factor
B) Integrating the dose rate over the integration period (50 years for adults) after intake
C) Summing the organ dose from all external exposures
D) Measuring the surface dose with a survey meter
Answer: B) Integrating the dose rate over the integration period (50 years for adults) after
intake
, Rationale: CDE reflects the total dose to a specific organ over the integration period after
intake.
12. A "Caution: Radiation Area" sign must be posted where an individual can receive:
A) More than 0.05 mSv (5 mrem) in 1 hour at 30 cm
B) More than 1 mSv (100 mrem) in 1 hour at 30 cm
C) More than 5 mSv (500 mrem) in 1 hour
D) More than 0.02 mSv (2 mrem) in 1 hour
Answer: A) More than 0.05 mSv (5 mrem) in 1 hour at 30 cm
Rationale: Radiation Area signs are seen at entrances to nuclear medicine labs where dose rates
exceed 5 mrem/hr.
13. A "High Radiation Area" requires posting where an individual can receive:
A) More than 0.05 mSv in 1 hour
B) More than 0.5 mSv in 1 hour
C) More than 1 mSv (100 mrem) in 1 hour at 30 cm
D) More than 5 mSv in 1 hour
Answer: C) More than 1 mSv (100 mrem) in 1 hour at 30 cm
Rationale: High Radiation Areas are commonly where radiation therapy is performed.
14. An "Unrestricted Area" is defined as an area where an individual receives less than:
A) 0.02 mSv (2 mrem) in 1 hour
B) 0.05 mSv (5 mrem) in 1 hour
C) 1 mSv in 1 hour
D) 0.5 mSv in 1 hour
Answer: A) 0.02 mSv (2 mrem) in 1 hour
Rationale: Reception and waiting areas typically qualify as unrestricted areas.
15. The quality factor (Q) for beta radiation is:
A) 1
B) 2
C) 5
D) 20
Answer: A) 1
Rationale: Beta particles have a quality factor of 1, meaning 1 Gy = 1 Sv.
16. The quality factor (Q) for alpha radiation is:
A) 1
B) 5
Actual Exam 2026/2027 Prep Questions
Complete Accurate Exam Approved
Questions And Correct Verified Solutions
With Detailed Rationales (100% Correct
Verified Answers)
1. What is the NRC annual occupational dose limit for the total effective dose equivalent
(TEDE) to the whole body?
A) 0.5 rem (5 mSv)
B) 5 rem (50 mSv)
C) 50 rem (500 mSv)
D) 100 rem (1 Sv)
Answer: B) 5 rem (50 mSv)
Rationale: 10 CFR 20.1201 establishes 5 rem (50 mSv) TEDE as the annual occupational limit for
whole body exposure.
2. The annual dose limit for the lens of the eye for an occupational worker under NRC
regulations is:
A) 5 rem (50 mSv)
B) 15 rem (150 mSv)
C) 50 rem (500 mSv)
D) 1 rem (10 mSv)
Answer: B) 15 rem (150 mSv)
Rationale: NRC sets the lens of the eye limit at 15 rem/year. Note: ICRP recommends 2 rem (20
mSv)/year, but NRC has not adopted this change.
3. The shallow dose equivalent (SDE) is used to monitor dose to:
A) The whole body
B) The lens of the eye
,C) The skin and extremities
D) Deep organs
Answer: C) The skin and extremities
Rationale: SDE measures dose at a depth of 0.007 cm (7 mg/cm²), typically assessed with ring
dosimeters.
4. The dose limit for a declared pregnant radiation worker (fetus) is:
A) 0.5 mSv per month
B) 5 mSv (0.5 rem) total for the gestation period
C) 50 mSv (5 rem) total for the gestation period
D) 1 mSv per week
Answer: B) 5 mSv (0.5 rem) total for the gestation period
Rationale: NRC requires that the fetal dose not exceed 5 mSv (0.5 rem) for the entire gestation
period.
5. What is the annual occupational dose limit for the skin or any extremity?
A) 5 rem (50 mSv)
B) 15 rem (150 mSv)
C) 50 rem (500 mSv)
D) 100 rem (1 Sv)
Answer: C) 50 rem (500 mSv)
Rationale: Extremity dose limit is 50 rem/year.
6. The annual dose limit for a member of the general public (continuous exposure) is:
A) 0.1 rem (1 mSv)
B) 0.5 rem (5 mSv)
C) 5 rem (50 mSv)
D) 1 rem (10 mSv)
Answer: A) 0.1 rem (1 mSv)
Rationale: Public dose limits are significantly lower than occupational limits.
7. The committed effective dose equivalent (CEDE) refers to:
A) Dose from a single external exposure event
B) Dose integrated over 50 years for adults after intake of radionuclides
C) Dose to the skin only
D) Dose to the fetus only
,Answer: B) Dose integrated over 50 years for adults after intake of radionuclides
Rationale: CEDE accounts for the total stochastic risk from internally deposited radionuclides
over the integration period.
8. The deep dose equivalent (DDE) is measured at what depth in tissue?
A) 0.007 cm
B) 0.3 cm
C) 1 cm
D) 5 cm
Answer: C) 1 cm
Rationale: DDE corresponds to dose at 1 cm depth, representing whole-body exposure from
penetrating radiation.
9. Which dosimeter type uses thermally stimulated luminescence to record dose?
A) Film badge
B) TLD (Thermoluminescent dosimeter)
C) OSL (Optically stimulated luminescence) badge
D) Electronic personal dosimeter
Answer: B) TLD
Rationale: TLDs store energy in crystal lattice defects and release light when heated
proportional to absorbed dose.
10. 1 mSv equals how many mrem?
A) 10 mrem
B) 100 mrem
C) 1000 mrem
D) 0.1 mrem
Answer: B) 100 mrem
Rationale: Conversion factor: 1 Sv = 100 rem; therefore 1 mSv = 100 mrem.
11. The committed dose equivalent (CDE) for an organ is calculated by:
A) Multiplying the absorbed dose by a tissue weighting factor
B) Integrating the dose rate over the integration period (50 years for adults) after intake
C) Summing the organ dose from all external exposures
D) Measuring the surface dose with a survey meter
Answer: B) Integrating the dose rate over the integration period (50 years for adults) after
intake
, Rationale: CDE reflects the total dose to a specific organ over the integration period after
intake.
12. A "Caution: Radiation Area" sign must be posted where an individual can receive:
A) More than 0.05 mSv (5 mrem) in 1 hour at 30 cm
B) More than 1 mSv (100 mrem) in 1 hour at 30 cm
C) More than 5 mSv (500 mrem) in 1 hour
D) More than 0.02 mSv (2 mrem) in 1 hour
Answer: A) More than 0.05 mSv (5 mrem) in 1 hour at 30 cm
Rationale: Radiation Area signs are seen at entrances to nuclear medicine labs where dose rates
exceed 5 mrem/hr.
13. A "High Radiation Area" requires posting where an individual can receive:
A) More than 0.05 mSv in 1 hour
B) More than 0.5 mSv in 1 hour
C) More than 1 mSv (100 mrem) in 1 hour at 30 cm
D) More than 5 mSv in 1 hour
Answer: C) More than 1 mSv (100 mrem) in 1 hour at 30 cm
Rationale: High Radiation Areas are commonly where radiation therapy is performed.
14. An "Unrestricted Area" is defined as an area where an individual receives less than:
A) 0.02 mSv (2 mrem) in 1 hour
B) 0.05 mSv (5 mrem) in 1 hour
C) 1 mSv in 1 hour
D) 0.5 mSv in 1 hour
Answer: A) 0.02 mSv (2 mrem) in 1 hour
Rationale: Reception and waiting areas typically qualify as unrestricted areas.
15. The quality factor (Q) for beta radiation is:
A) 1
B) 2
C) 5
D) 20
Answer: A) 1
Rationale: Beta particles have a quality factor of 1, meaning 1 Gy = 1 Sv.
16. The quality factor (Q) for alpha radiation is:
A) 1
B) 5
