NMTCB(RS) Radiation Safety Specialty

According to 10 CFR 20, what is the annual occupational dose limit for the total effective dose equivalent (TEDE) to the whole body?

• A5 rem (0.05 Sv)
• B50 rem (0.5 Sv)
• C0.5 rem (5 mSv)
• D100 rem (1 Sv)

What does the acronym ALARA stand for in radiation protection?

• AAs Low As Reasonably Achievable
• BAbsolute Lowest Allowable Radiation Amount
• CAs Limited As Readily Available
• DAnnual Limit for Authorized Radiation Activities

Which of the following is the correct half-life of Technetium-99m (Tc-99m)?

• A6 hours
• B12 hours
• C8 days
• D73 hours

According to the inverse square law, if the exposure rate at 1 meter from a point source is 100 mR/hr, what is the exposure rate at 2 meters?

• A50 mR/hr
• B25 mR/hr
• C200 mR/hr
• D10 mR/hr

What are the three fundamental principles of radiation protection for external sources?

• ATime, distance, and shielding
• BContainment, ventilation, and monitoring
• CDose, dose-rate, and activity
• DDetection, measurement, and recording

Under 10 CFR 35.3045, when does a therapeutic radiopharmaceutical administration to an organ or tissue other than the treatment site constitute a reportable medical event?

• AWhen the dose to that site exceeds 0.5 Sv (50 rem) and exceeds 50% of the expected dose i…
• BWhen any dose exceeds 0.05 Sv (5 rem) to any organ regardless of the prescribed dose
• CWhen the prescribed dose differs by more than 5%
• DAny radiation exposure to a member of the public

What type of radiation does Iodine-131 primarily emit that makes it useful for thyroid therapy?

• AAlpha particles
• BBeta particles
• CNeutrons
• DPositrons

What is the annual dose limit for the lens of the eye for occupational radiation workers under current NRC regulations?

• A15 rem (0.15 Sv)
• B5 rem (0.05 Sv)
• C50 rem (0.5 Sv)
• D1 rem (0.01 Sv)

What is the purpose of a wipe test (swipe test) in a nuclear medicine department?

• ATo detect removable radioactive contamination on surfaces
• BTo calibrate the dose calibrator
• CTo measure ambient radiation exposure rates
• DTo verify the identity of a radiopharmaceutical

Which of the following is the correct DOT shipping label for a package containing radioactive material with a transport index greater than 1 but not exceeding 10?

• ARadioactive White-I
• BRadioactive Yellow-II
• CRadioactive Yellow-III
• DRadioactive Red-IV

What is the maximum surface dose rate allowed for a Radioactive White-I labeled package?

• A0.5 mrem/hr
• B5 mrem/hr
• C50 mrem/hr
• D200 mrem/hr

What instrument is most appropriate for measuring the activity of a radiopharmaceutical dose before patient administration?

• AGeiger-Mueller counter
• BDose calibrator (ionization chamber)
• CSodium iodide well counter
• DPocket dosimeter

A patient receives 150 mCi of I-131 for thyroid cancer therapy. According to NRC regulations, the patient may be released when the measured dose rate at 1 meter is at or below which value?

• A7 mrem/hr
• B2 mrem/hr
• C0.5 mrem/hr
• D25 mrem/hr

What is the primary responsibility of a Radiation Safety Officer (RSO)?

• APerforming all radiation surveys personally
• BOverseeing the radiation safety program and ensuring regulatory compliance
• CAdministering all radiopharmaceutical doses to patients
• DCalibrating all radiation detection instruments

Under 10 CFR 19.12, which of the following must be provided to radiation workers?

• AA personal vehicle for commuting
• BInstructions on radiation risks, protective measures, and applicable regulations
• CFree medical insurance for radiation-related illnesses
• DAnnual salary increases based on radiation exposure

Which type of personal dosimeter provides an immediate (real-time) dose reading?

• AFilm badge
• BOptically stimulated luminescence (OSL) dosimeter
• CElectronic personal dosimeter (EPD)
• DThermoluminescent dosimeter (TLD)

A radioactive source has an initial activity of 20 mCi. What is the remaining activity after 3 half-lives?

• A10 mCi
• B5 mCi
• C2.5 mCi
• D6.67 mCi

Which of the following radionuclides is an alpha emitter used in the treatment of castration-resistant prostate cancer with bone metastases?

• AIodine-131
• BLutetium-177
• CRadium-223
• DYttrium-90

A nuclear medicine technologist spills a small amount of Tc-99m on the countertop. What is the first step in the spill response?

• ALeave the area and call the fire department
• BNotify the RSO, contain the spill, and prevent spread
• CContinue working and clean up at the end of the day
• DEvacuate the entire building

What is the half-value layer (HVL)?

• AThe thickness of material that reduces radiation intensity by half
• BThe time required for activity to decrease by half
• CThe distance at which radiation dose is halved
• DThe energy at which half of the photons are absorbed

What is the annual dose limit for a declared pregnant radiation worker under 10 CFR 20?

• A0.5 rem (5 mSv) over the entire pregnancy
• B5 rem (50 mSv) per year
• C1 rem (10 mSv) per year
• D0.1 rem (1 mSv) over the entire pregnancy

What is the primary advantage of Lutetium-177 (Lu-177) over Yttrium-90 (Y-90) for peptide receptor radionuclide therapy (PRRT)?

• ALu-177 has a higher maximum beta energy
• BLu-177 emits gamma rays suitable for post-therapy imaging and has a shorter tissue range,…
• CLu-177 has a shorter half-life allowing quicker patient release
• DLu-177 does not require any radiation safety precautions

According to 10 CFR 20, what radiation level defines a "High Radiation Area"?

• AAn area where the dose rate exceeds 5 mrem/hr at 30 cm
• BAn area where the dose rate exceeds 100 mrem/hr at 30 cm from the source
• CAn area where the dose rate exceeds 500 mrem/hr at 30 cm
• DAn area where the dose rate exceeds 1,000 mrem/hr at 30 cm

Which organization establishes the transportation requirements for radioactive materials shipped by ground in the United States?

• AThe Nuclear Regulatory Commission (NRC)
• BThe Department of Transportation (DOT)
• CThe Environmental Protection Agency (EPA)
• DThe Food and Drug Administration (FDA)

What is the required frequency for performing constancy testing on a dose calibrator?

• ADaily, before first use
• BWeekly
• CMonthly
• DAnnually

Stochastic effects of radiation are best described as:

• AEffects whose severity increases with dose, with a threshold
• BEffects whose probability of occurrence increases with dose, with no threshold
• CEffects that occur only above 100 rem
• DEffects that are immediate and deterministic in nature

A package of radioactive material arrives at the hospital. Under 10 CFR 20.1906, within what time frame must the package be monitored for surface contamination and radiation levels?

• AWithin 3 hours of receipt during normal business hours
• BWithin 24 hours of receipt
• CWithin 1 hour of receipt
• DWithin 7 days of receipt

What type of radiation interaction predominates at diagnostic imaging energies (30-150 keV) in soft tissue?

• APair production
• BCompton scattering
• CPhotoelectric effect
• DCoherent (Rayleigh) scattering

What is the NRC requirement for records retention of personnel radiation exposure (dose) records?

• A5 years after the last recorded dose
• BUntil the NRC authorizes their disposal
• C10 years after the worker leaves employment
• D3 years after the last recorded dose

What is the regulatory basis for allowing a patient treated with radioactive material to be released if the total effective dose equivalent (TEDE) to any other individual is unlikely to exceed which value?

• A5 mSv (500 mrem)
• B1 mSv (100 mrem)
• C50 mSv (5 rem)
• D0.5 mSv (50 mrem)

In the context of radiation biology, what is the oxygen enhancement ratio (OER)?

• AThe ratio of radiation dose required in anoxic conditions to that in oxygenated condition…
• BThe percentage of oxygen dissolved in blood during radiation exposure
• CThe ratio of radiosensitivity between cancerous and normal tissues
• DThe enhancement of radiation dose by administering supplemental oxygen

What category of radioactive waste must be held for decay before disposal as non-radioactive waste?

• AHigh-level waste only
• BShort-lived radioactive waste with half-lives less than or equal to 120 days
• CAll radioactive waste regardless of half-life
• DOnly waste containing alpha emitters

What is the minimum number of half-lives that radioactive waste should typically be held before surveying for disposal as non-radioactive waste?

• A5 half-lives
• B10 half-lives
• C3 half-lives
• D20 half-lives

Under NRC regulations, who is an "authorized user" for the medical use of byproduct material?

• AAny medical professional with a state medical license
• BA physician who meets specific training and experience requirements and is named on the r…
• CAny nuclear medicine technologist certified by the NMTCB
• DThe hospital's chief medical officer

What type of survey meter is most sensitive for detecting low levels of radioactive contamination?

• AIonization chamber
• BPressurized ion chamber (cutie pie)
• CGeiger-Mueller (GM) counter with a thin-window pancake probe
• DProportional counter used only for neutron detection

What is the primary radiation safety concern when administering Ra-223 (Radium-223 dichloride) therapy?

• AHigh external gamma exposure to staff
• BAlpha contamination from patient body fluids, requiring standard contamination precautions
• CSignificant neutron emission requiring thick shielding
• DVolatile radioactive gas production requiring special ventilation

When performing I-131 therapy for thyroid cancer, which of the following shielding materials is most appropriate for reducing exposure to beta radiation?

• ALead
• BLucite (acrylic/plexiglass)
• CTungsten
• DDepleted uranium

What is a "reportable medical event" regarding therapeutic administration of a radiopharmaceutical per 10 CFR 35.3045?

• AAny therapeutic administration that results in patient discomfort
• BA delivered dose that differs from the prescribed dose by 20% or more while also exceedin…
• CAny nuclear medicine procedure lasting more than 2 hours
• DA dose that differs from the prescribed dose by more than 50% only

How must a medical event be reported to the NRC according to 10 CFR 35.3045?

• ABy telephone within 24 hours and a written report within 15 days
• BBy written report within 30 days only
• CBy telephone immediately and written report within 5 days
• DBy telephone within 1 calendar day and written report within 15 calendar days

What is the maximum permissible dose rate at the surface of a Radioactive Yellow-III package?

• A50 mrem/hr
• B100 mrem/hr
• C200 mrem/hr
• D500 mrem/hr

What is the NRC requirement for security of portable radioactive sources when not in use?

• AThey may be left on any countertop as long as the room is locked
• BThey must be secured against unauthorized removal or access
• CNo specific security requirements exist
• DThey need only be labeled, not physically secured

What is the effective dose (E) formula using tissue weighting factors?

• AE = Σ wT × HT, where wT is the tissue weighting factor and HT is the equivalent dose to t…
• BE = Total activity × half-life
• CE = Exposure rate × distance²
• DE = Absorbed dose × quality factor for the whole body only

What is the linear energy transfer (LET) characteristic of alpha particles compared to gamma rays?

• AAlpha particles have lower LET than gamma rays
• BAlpha particles and gamma rays have equal LET
• CAlpha particles have higher LET than gamma rays
• DLET does not apply to alpha particles

What is the radiation weighting factor (wR) for alpha particles used in calculating equivalent dose?

• A1
• B5
• C10
• D20

What is the required frequency for performing linearity testing on a dose calibrator?

• ADaily
• BWeekly
• CQuarterly
• DAnnually

A major radioactive spill has occurred involving a large quantity of I-131 in a hot lab. What is the FIRST action to take?

• ABegin decontamination immediately
• BSecure the area, evacuate personnel, and notify the RSO
• CCall the NRC Operations Center
• DTake wipe tests of the spill area

What is the SI unit of absorbed dose?

• ASievert (Sv)
• BGray (Gy)
• CBecquerel (Bq)
• DCoulomb per kilogram (C/kg)