TEXAS INDUSTRIAL RADIOGRAPHER CERTIFICATION PRACTICE EXAM QUESTIONS AND
CORRECT ANSWERS (VERIFIED ANSWERS) PLUS RATIONALES 2026 Q&A |LATEST EXAM
UPDATE 2026/2027
Section One: Questions 1–100
Which of the following defines the inverse square law as it applies to radiation protection?
A. The intensity of radiation is directly proportional to the square of the distance from the source.
B. The intensity of radiation is inversely proportional to the square of the distance from the source.
C. The dose rate decreases linearly as the distance from the source increases.
D. The dose rate increases exponentially with distance from the source.
🟢 B. The intensity of radiation is inversely proportional to the square of the distance from the
source.
🔴 RATIONALE: The inverse square law dictates that doubling the distance from a point source
reduces the radiation intensity to one-fourth of its original value.
Under Texas Regulations for Control of Radiation (TRCR), what is the annual occupational dose
limit for the whole body of an adult radiographer?
A. 1 rem (10 mSv)
B. 3 rem (30 mSv)
C. 5 rem (50 mSv)
D. 50 rem (500 mSv)
🟢 C. 5 rem (50 mSv)
🔴 RATIONALE: The Texas Department of State Health Services (DSHS) enforces an annual
occupational total effective dose equivalent (TEDE) limit of 5 rem (50 mSv) for adult radiation
workers.
An industrial radiographer notes that a survey meter reads 120 mR/hr at a distance of 2 feet from a
source. What will the exposure rate be at a distance of 4 feet?
,A. 60 mR/hr
B. 45 mR/hr
C. 30 mR/hr
D. 15 mR/hr
🟢 C. 30 mR/hr
🔴 RATIONALE: According to the inverse square law, doubling the distance from 2 feet to 4 feet
reduces the intensity by a factor of 4 (120 ÷ 4 = 30).
What type of personnel monitoring device provides an immediate, real-time readout of radiation
exposure?
A. Thermoluminescent Dosimeter (TLD)
B. Optically Stimulated Luminescence (OSL) dosimeter
C. Direct Reading Pocket Dosimeter (DRD)
D. Film badge
🟢 C. Direct Reading Pocket Dosimeter (DRD)
🔴 RATIONALE: Pocket dosimeters allow the radiographer to check their accumulated dose
instantly in the field, unlike passive monitors like TLDs or OSLs which require laboratory
processing.
Which isotope is most commonly utilized in industrial gamma radiography for inspecting thick-
walled steel components?
A. Iridium-192
B. Cobalt-60
C. Cesium-137
D. Selenium-75
🟢 B. Cobalt-60
🔴 RATIONALE: Cobalt-60 emits high-energy gamma rays (1.17 and 1.33 MeV), making it suitable
,for penetrating very thick steel objects (2.5 to 9 inches), whereas Iridium-192 is used for thinner
materials.
During a radiographic exposure, a radiographer notices a member of the public entering the
restricted area boundary. What is the immediate correct action?
A. Yell at the individual to turn around and leave immediately.
B. Finish the remaining exposure time quickly while monitoring the individual.
C. Terminate the exposure immediately by retracting the source into the exposure device.
D. Walk over to the individual to explain the hazards of industrial radiography.
🟢 C. Terminate the exposure immediately by retracting the source into the exposure device.
🔴 RATIONALE: Public safety is paramount; the source must be secured immediately in its
shielded housing to eliminate the radiation field before addressing the intrusion.
What is the half-life of the radioactive isotope Iridium-192?
A. 30 days
B. 74 days
C. 5.3 years
D. 30 years
🟢 B. 74 days
🔴 RATIONALE: Iridium-192 has a half-life of approximately 74 days, requiring frequent source
replacements or adjustments to exposure charts over time.
According to Texas regulatory requirements, what is the maximum radiation level permitted at the
external surface of a storage container or transport package under a non-exclusive use shipment?
A. 2 mR/hr
B. 50 mR/hr
C. 200 mR/hr
D. 1000 mR/hr
, 🟢 C. 200 mR/hr
🔴 RATIONALE: Department of Transportation (DOT) and Texas regulations mandate that
transport packages cannot exceed 200 mR/hr at the surface of the package during standard
transport.
What is the primary purpose of using a collimator during radiographic exposures?
A. To increase the energy of the primary beam.
B. To reduce the exposure time required for a high-quality radiograph.
C. To restrict the radiation beam to a useful local area and minimize scatter radiation.
D. To filter out low-energy beta particles emitted by the source.
🟢 C. To restrict the radiation beam to a useful local area and minimize scatter radiation.
🔴 RATIONALE: Collimators are directional shields made of dense materials like tungsten or lead
that limit the radiation beam to the intended direction, protecting the operator and public.
If a pocket dosimeter becomes discharged or goes "off-scale" during a radiography shift, what must
the radiographer do?
A. Tap the dosimeter gently to see if the scale resets itself.
B. Estimate the dose received, record it, and finish the shift.
C. Stop work immediately, turn in passive monitoring devices for emergency processing, and notify
the RSO.
D. Re-zero the dosimeter using the charger and continue the exposure.
🟢 C. Stop work immediately, turn in passive monitoring devices for emergency processing, and
notify the RSO.
🔴 RATIONALE: An off-scale pocket dosimeter indicates a potential overexposure; operations
must cease immediately so the exact dose can be verified through passive badge processing.
CORRECT ANSWERS (VERIFIED ANSWERS) PLUS RATIONALES 2026 Q&A |LATEST EXAM
UPDATE 2026/2027
Section One: Questions 1–100
Which of the following defines the inverse square law as it applies to radiation protection?
A. The intensity of radiation is directly proportional to the square of the distance from the source.
B. The intensity of radiation is inversely proportional to the square of the distance from the source.
C. The dose rate decreases linearly as the distance from the source increases.
D. The dose rate increases exponentially with distance from the source.
🟢 B. The intensity of radiation is inversely proportional to the square of the distance from the
source.
🔴 RATIONALE: The inverse square law dictates that doubling the distance from a point source
reduces the radiation intensity to one-fourth of its original value.
Under Texas Regulations for Control of Radiation (TRCR), what is the annual occupational dose
limit for the whole body of an adult radiographer?
A. 1 rem (10 mSv)
B. 3 rem (30 mSv)
C. 5 rem (50 mSv)
D. 50 rem (500 mSv)
🟢 C. 5 rem (50 mSv)
🔴 RATIONALE: The Texas Department of State Health Services (DSHS) enforces an annual
occupational total effective dose equivalent (TEDE) limit of 5 rem (50 mSv) for adult radiation
workers.
An industrial radiographer notes that a survey meter reads 120 mR/hr at a distance of 2 feet from a
source. What will the exposure rate be at a distance of 4 feet?
,A. 60 mR/hr
B. 45 mR/hr
C. 30 mR/hr
D. 15 mR/hr
🟢 C. 30 mR/hr
🔴 RATIONALE: According to the inverse square law, doubling the distance from 2 feet to 4 feet
reduces the intensity by a factor of 4 (120 ÷ 4 = 30).
What type of personnel monitoring device provides an immediate, real-time readout of radiation
exposure?
A. Thermoluminescent Dosimeter (TLD)
B. Optically Stimulated Luminescence (OSL) dosimeter
C. Direct Reading Pocket Dosimeter (DRD)
D. Film badge
🟢 C. Direct Reading Pocket Dosimeter (DRD)
🔴 RATIONALE: Pocket dosimeters allow the radiographer to check their accumulated dose
instantly in the field, unlike passive monitors like TLDs or OSLs which require laboratory
processing.
Which isotope is most commonly utilized in industrial gamma radiography for inspecting thick-
walled steel components?
A. Iridium-192
B. Cobalt-60
C. Cesium-137
D. Selenium-75
🟢 B. Cobalt-60
🔴 RATIONALE: Cobalt-60 emits high-energy gamma rays (1.17 and 1.33 MeV), making it suitable
,for penetrating very thick steel objects (2.5 to 9 inches), whereas Iridium-192 is used for thinner
materials.
During a radiographic exposure, a radiographer notices a member of the public entering the
restricted area boundary. What is the immediate correct action?
A. Yell at the individual to turn around and leave immediately.
B. Finish the remaining exposure time quickly while monitoring the individual.
C. Terminate the exposure immediately by retracting the source into the exposure device.
D. Walk over to the individual to explain the hazards of industrial radiography.
🟢 C. Terminate the exposure immediately by retracting the source into the exposure device.
🔴 RATIONALE: Public safety is paramount; the source must be secured immediately in its
shielded housing to eliminate the radiation field before addressing the intrusion.
What is the half-life of the radioactive isotope Iridium-192?
A. 30 days
B. 74 days
C. 5.3 years
D. 30 years
🟢 B. 74 days
🔴 RATIONALE: Iridium-192 has a half-life of approximately 74 days, requiring frequent source
replacements or adjustments to exposure charts over time.
According to Texas regulatory requirements, what is the maximum radiation level permitted at the
external surface of a storage container or transport package under a non-exclusive use shipment?
A. 2 mR/hr
B. 50 mR/hr
C. 200 mR/hr
D. 1000 mR/hr
, 🟢 C. 200 mR/hr
🔴 RATIONALE: Department of Transportation (DOT) and Texas regulations mandate that
transport packages cannot exceed 200 mR/hr at the surface of the package during standard
transport.
What is the primary purpose of using a collimator during radiographic exposures?
A. To increase the energy of the primary beam.
B. To reduce the exposure time required for a high-quality radiograph.
C. To restrict the radiation beam to a useful local area and minimize scatter radiation.
D. To filter out low-energy beta particles emitted by the source.
🟢 C. To restrict the radiation beam to a useful local area and minimize scatter radiation.
🔴 RATIONALE: Collimators are directional shields made of dense materials like tungsten or lead
that limit the radiation beam to the intended direction, protecting the operator and public.
If a pocket dosimeter becomes discharged or goes "off-scale" during a radiography shift, what must
the radiographer do?
A. Tap the dosimeter gently to see if the scale resets itself.
B. Estimate the dose received, record it, and finish the shift.
C. Stop work immediately, turn in passive monitoring devices for emergency processing, and notify
the RSO.
D. Re-zero the dosimeter using the charger and continue the exposure.
🟢 C. Stop work immediately, turn in passive monitoring devices for emergency processing, and
notify the RSO.
🔴 RATIONALE: An off-scale pocket dosimeter indicates a potential overexposure; operations
must cease immediately so the exact dose can be verified through passive badge processing.
