RHS practice test 2026 UPDATED ACTUAL
Questions and CORRECT Answers
Using the ALARA concept as a guideline for radiographs includes all of the following EXCEPT
A. draping the patient with a thyroid collar.
B. using a circular PID.
C. draping the patient with a lead apron.
D. using a rectangular PID. - CORRECT ANSWER -B. using a circular PID.
Which of the following errors occur when the vertical angulation is incorrect?
A. Cone cut
B. Blurred image
C. Elongation
D. Overlapping - CORRECT ANSWER -C. Elongation
Which of the following was established to address the education and certification of operators of radiographic equipment?
A. Radiation Control for Health and Safety
B. National Council on Radiation Protection and Measurements
C. Consumer-Patient Radiation Health and Safety Act
D. International Commission on Radiation Units and Measurements - CORRECT ANSWER -C. Consumer-Patient
Radiation Health and Safety Act
Which of the following protection techniques is used to minimize x-radiation exposure to the operator?
A. Structural shielding
B. Wearing a lead line apron
C. Wearing a dosimeter
D. Standing next to the tubehead - CORRECT ANSWER -A. Structural shielding
When changing the 8-inch PID to a 16-inch PID, which of the following is used to determine the intensity of the beam?
A. Rule of isometry
B. Inverse square law
C. Exposure chart
D. SLOB rule - CORRECT ANSWER -B. Inverse square law
Before exposing radiographs on a minor, the dental assistant should
A. obtain consent from parent or legal guardian.
B. explain radiographs are mandatory for all patients.
C. explain radiographs are required by insurance.
D. obtain consent from the patient. - CORRECT ANSWER -A. obtain consent from parent or legal guardian.
Which of the following helps to decrease exposure of the thyroid gland from the primary radiation beam?
A. Bisecting angle technique
B. Use of round collimation
C. Paralleling technique
D. Decreasing the x-ray focal plane - CORRECT ANSWER -C. Paralleling technique
The maximum permissible dose (MPD) of ionizing radiation for occupational exposure is
A. 5.0 rem per year.
B. 0.05 rem per year.
C. 0.5 rem per year.
D. 1.0 rem per year. - CORRECT ANSWER -A. 5.0 rem per year.
Which of the following pathogens is NOT found in oral or respiratory secretions?
A. Mycobacterium tuberculosis
B. Hepatitis B virus
C. Flu virus
D. West Nile virus - CORRECT ANSWER -D. West Nile virus
,The most common reason for taking bitewing radiographs is to evaluate
A. occlusal caries.
B. incipient caries.
C. calculus.
D. interproximal caries. - CORRECT ANSWER -D. interproximal caries.
How often should protective clothing be changed in an oral healthcare setting?
A. Twice daily
B. After each patient
C. Once weekly
D. When visibly soiled - CORRECT ANSWER -D. When visibly soiled
Where is the most common area in the oral cavity for a dentigerous cyst?
A. Between the central incisors
B. Around the canines
C. Around the third molars
D. Between the premolars - CORRECT ANSWER -C. Around the third molars
Which of the following measures the amount of radiation that reaches the surface of the skin?
A. Dose rate
B. Quality factor
C. Mitotic activity
D. Roentgen - CORRECT ANSWER -D. Roentgen
If there are no teeth to serve as guides, which of the following landmarks indicates a maxillary molar area radiograph?
A. Tuberosity
B. Incisive foramen
C. Mental foramen
D. Internal oblique ridge - CORRECT ANSWER -A. Tuberosity
Which of the following PID produces the greatest amount of secondary radiation?
A. Open-end lead-lined cylinder
B. Open-end lead-lined rectangular
C. Closed-end plastic cone
D. Closed-end aluminum cylinder - CORRECT ANSWER -C. Closed-end plastic cone
The penetrating x-ray beam produced during dental radiography is called
A. characteristic radiation.
B. scatter radiation.
C. primary radiation.
D. secondary radiation. - CORRECT ANSWER -C. primary radiation.
To prevent cross-contamination, wipe the counter top with
A. an EPA-approved disinfectant.
B. alcohol wipes.
C. bleach solution.
D. soap and water. - CORRECT ANSWER -A. an EPA-approved disinfectant.
What is the primary advantage in using digital radiography?
A. Reduces the radiation to patient
B. Increases comfort for the patient
C. Increases image density
D. Reduces image contrast - CORRECT ANSWER -A. Reduces the radiation to patient
The occlusal plane will appear diagonal in the radiograph when there is a/an
A. incorrect vertical angulation.
B. poor horizontal angulation.
C. incorrect film placement.
D. bent film corner. - CORRECT ANSWER -C. incorrect film placement.
, Personnel monitoring for radiation exposure is done by
A. observing physical changes over time.
B. wearing a dosimeter.
C. documenting the number of exposures.
D. reporting exposures to the state. - CORRECT ANSWER -B. wearing a dosimeter.
The amount of radiation and exposure time needed to produce a diagnostic radiograph is best determined by
A. kVp.
B. mA.
C. film size.
D. film speed. - CORRECT ANSWER -D. film speed.
Foreshortening of the maxillary radiographic image results from
A. increased horizontal angulation.
B. decreased horizontal angulation.
C. decreased vertical angulation.
D. increased vertical angulation. - CORRECT ANSWER -D. increased vertical angulation.
Which of the following would you adjust to produce wavelengths with the greatest penetrating power?
A. Distance
B. mA
C. kVp
D. Time - CORRECT ANSWER -C. kVp
Which of the following affects the quantity of x-rays being emitted from the tubehead?
A. kVp
B. Impulse
C. Filtration
D. mA - CORRECT ANSWER -D. mA
Patients should wear a thyroid collar during which type of radiographic exposure?
A. Extraoral radiograph
B. Panoramic radiograph
C. Intraoral radiograph
D. Cephalometric radiograph - CORRECT ANSWER -C. Intraoral radiograph
What size film, when placed vertically in the anterior region of the mouth, is most effective for evaluating caries and
periodontal health?
A. 0
B. 4
C. 2
D. 3 - CORRECT ANSWER -C. 2
Which of the following landmarks is useful when mounting films in the maxillary posterior area?
A. Inferior nasal conchae
B. Internal oblique ridge
C. Floor of the maxillary sinus
D. External oblique ridge - CORRECT ANSWER -C. Floor of the maxillary sinus
Cone beam computed tomography uses
A. 3-dimensional technology.
B. customized film holders.
C. 8 x 10 extraoral film.
D. panoramic cassettes. - CORRECT ANSWER -A. 3-dimensional technology.
To help desensitize the tissue prior to film placement, the dental assistant should
A. place the film in dental assistant's's mouth to demonstrate.
B. touch the palate with the film.
C. expose the most anterior film first.
Questions and CORRECT Answers
Using the ALARA concept as a guideline for radiographs includes all of the following EXCEPT
A. draping the patient with a thyroid collar.
B. using a circular PID.
C. draping the patient with a lead apron.
D. using a rectangular PID. - CORRECT ANSWER -B. using a circular PID.
Which of the following errors occur when the vertical angulation is incorrect?
A. Cone cut
B. Blurred image
C. Elongation
D. Overlapping - CORRECT ANSWER -C. Elongation
Which of the following was established to address the education and certification of operators of radiographic equipment?
A. Radiation Control for Health and Safety
B. National Council on Radiation Protection and Measurements
C. Consumer-Patient Radiation Health and Safety Act
D. International Commission on Radiation Units and Measurements - CORRECT ANSWER -C. Consumer-Patient
Radiation Health and Safety Act
Which of the following protection techniques is used to minimize x-radiation exposure to the operator?
A. Structural shielding
B. Wearing a lead line apron
C. Wearing a dosimeter
D. Standing next to the tubehead - CORRECT ANSWER -A. Structural shielding
When changing the 8-inch PID to a 16-inch PID, which of the following is used to determine the intensity of the beam?
A. Rule of isometry
B. Inverse square law
C. Exposure chart
D. SLOB rule - CORRECT ANSWER -B. Inverse square law
Before exposing radiographs on a minor, the dental assistant should
A. obtain consent from parent or legal guardian.
B. explain radiographs are mandatory for all patients.
C. explain radiographs are required by insurance.
D. obtain consent from the patient. - CORRECT ANSWER -A. obtain consent from parent or legal guardian.
Which of the following helps to decrease exposure of the thyroid gland from the primary radiation beam?
A. Bisecting angle technique
B. Use of round collimation
C. Paralleling technique
D. Decreasing the x-ray focal plane - CORRECT ANSWER -C. Paralleling technique
The maximum permissible dose (MPD) of ionizing radiation for occupational exposure is
A. 5.0 rem per year.
B. 0.05 rem per year.
C. 0.5 rem per year.
D. 1.0 rem per year. - CORRECT ANSWER -A. 5.0 rem per year.
Which of the following pathogens is NOT found in oral or respiratory secretions?
A. Mycobacterium tuberculosis
B. Hepatitis B virus
C. Flu virus
D. West Nile virus - CORRECT ANSWER -D. West Nile virus
,The most common reason for taking bitewing radiographs is to evaluate
A. occlusal caries.
B. incipient caries.
C. calculus.
D. interproximal caries. - CORRECT ANSWER -D. interproximal caries.
How often should protective clothing be changed in an oral healthcare setting?
A. Twice daily
B. After each patient
C. Once weekly
D. When visibly soiled - CORRECT ANSWER -D. When visibly soiled
Where is the most common area in the oral cavity for a dentigerous cyst?
A. Between the central incisors
B. Around the canines
C. Around the third molars
D. Between the premolars - CORRECT ANSWER -C. Around the third molars
Which of the following measures the amount of radiation that reaches the surface of the skin?
A. Dose rate
B. Quality factor
C. Mitotic activity
D. Roentgen - CORRECT ANSWER -D. Roentgen
If there are no teeth to serve as guides, which of the following landmarks indicates a maxillary molar area radiograph?
A. Tuberosity
B. Incisive foramen
C. Mental foramen
D. Internal oblique ridge - CORRECT ANSWER -A. Tuberosity
Which of the following PID produces the greatest amount of secondary radiation?
A. Open-end lead-lined cylinder
B. Open-end lead-lined rectangular
C. Closed-end plastic cone
D. Closed-end aluminum cylinder - CORRECT ANSWER -C. Closed-end plastic cone
The penetrating x-ray beam produced during dental radiography is called
A. characteristic radiation.
B. scatter radiation.
C. primary radiation.
D. secondary radiation. - CORRECT ANSWER -C. primary radiation.
To prevent cross-contamination, wipe the counter top with
A. an EPA-approved disinfectant.
B. alcohol wipes.
C. bleach solution.
D. soap and water. - CORRECT ANSWER -A. an EPA-approved disinfectant.
What is the primary advantage in using digital radiography?
A. Reduces the radiation to patient
B. Increases comfort for the patient
C. Increases image density
D. Reduces image contrast - CORRECT ANSWER -A. Reduces the radiation to patient
The occlusal plane will appear diagonal in the radiograph when there is a/an
A. incorrect vertical angulation.
B. poor horizontal angulation.
C. incorrect film placement.
D. bent film corner. - CORRECT ANSWER -C. incorrect film placement.
, Personnel monitoring for radiation exposure is done by
A. observing physical changes over time.
B. wearing a dosimeter.
C. documenting the number of exposures.
D. reporting exposures to the state. - CORRECT ANSWER -B. wearing a dosimeter.
The amount of radiation and exposure time needed to produce a diagnostic radiograph is best determined by
A. kVp.
B. mA.
C. film size.
D. film speed. - CORRECT ANSWER -D. film speed.
Foreshortening of the maxillary radiographic image results from
A. increased horizontal angulation.
B. decreased horizontal angulation.
C. decreased vertical angulation.
D. increased vertical angulation. - CORRECT ANSWER -D. increased vertical angulation.
Which of the following would you adjust to produce wavelengths with the greatest penetrating power?
A. Distance
B. mA
C. kVp
D. Time - CORRECT ANSWER -C. kVp
Which of the following affects the quantity of x-rays being emitted from the tubehead?
A. kVp
B. Impulse
C. Filtration
D. mA - CORRECT ANSWER -D. mA
Patients should wear a thyroid collar during which type of radiographic exposure?
A. Extraoral radiograph
B. Panoramic radiograph
C. Intraoral radiograph
D. Cephalometric radiograph - CORRECT ANSWER -C. Intraoral radiograph
What size film, when placed vertically in the anterior region of the mouth, is most effective for evaluating caries and
periodontal health?
A. 0
B. 4
C. 2
D. 3 - CORRECT ANSWER -C. 2
Which of the following landmarks is useful when mounting films in the maxillary posterior area?
A. Inferior nasal conchae
B. Internal oblique ridge
C. Floor of the maxillary sinus
D. External oblique ridge - CORRECT ANSWER -C. Floor of the maxillary sinus
Cone beam computed tomography uses
A. 3-dimensional technology.
B. customized film holders.
C. 8 x 10 extraoral film.
D. panoramic cassettes. - CORRECT ANSWER -A. 3-dimensional technology.
To help desensitize the tissue prior to film placement, the dental assistant should
A. place the film in dental assistant's's mouth to demonstrate.
B. touch the palate with the film.
C. expose the most anterior film first.
