Question 1

The roentgen unit is a measure of the:&#10;A) amount of fluorescence from screens&#10;B) number of ions created in air&#10;C) number of ions created in tissue&#10;D) amount of silver atoms on film

Accepted Answer

The roentgen unit is specifically a measure of the number of ions created in air by X-rays or gamma rays, indicating the ionizing capability of radiation in air, not in tissue or other materials.

Question 2

Total filtration in the X-ray tube must be the equivalent of at least:&#10;A) 2.5 mm aluminum&#10;B) 1.5 mm aluminum&#10;C) 0.5 mm aluminum&#10;D) 1.0 mm aluminum

Accepted Answer

Total filtration in the X-ray tube must be at least the equivalent of 2.5 mm aluminum, especially for machines operating above 70 kVp, to ensure patient safety by absorbing low-energy x-ray photons.

Question 3

The quality of an X-ray beam is determined by the:&#10;A) heat of the filament&#10;B) kVp&#10;C) mAs&#10;D) distance

Accepted Answer

The quality of an X-ray beam, which refers to the energy or penetrating ability of the X-ray photons, is primarily determined by the kilovoltage peak (kVp) setting. Higher kVp settings produce X-rays with higher energy levels, thus increasing their penetrating ability.

Question 4

The stage of life most sensitive to radiation is:&#10;A) fetus&#10;B) adult&#10;C) elderly&#10;D) all may be equally affected

Accepted Answer

The fetus is the most sensitive stage of life to radiation due to the rapid division and growth of cells, which makes them more susceptible to damage from radiation exposure.

Question 5

X-ray beam collimation is used because:&#10;A) image quality is improved&#10;B) patient dose is decreased&#10;C) scatter radiation is decreased&#10;D) all of the above

Accepted Answer

X-ray beam collimation improves image quality by reducing the area irradiated, thus decreasing scatter radiation which can blur the image. It also decreases patient dose by limiting the volume of tissue exposed to radiation.

Question 6

Radiation dose to the gonads may cause:&#10;A) somatic damage&#10;B) genetic damage&#10;C) cataracts&#10;D) bremsstrahlung

Accepted Answer

Radiation exposure to the gonads can cause genetic damage, affecting the DNA in sperm or eggs, which can then be passed on to future generations. Somatic damage refers to effects on the body cells other than reproductive cells, cataracts are a potential result of radiation exposure to the eye, and bremsstrahlung is a type of radiation produced when charged particles are decelerated.

Question 7

Personal dosimeters are designed to be worn:&#10;A) outside the lead apron near the neck&#10;B) inside the lead apron near the neck&#10;C) inside the lead apron during fluoroscopy&#10;D) inside the lead apron near the waist

Accepted Answer

Personal dosimeters are designed to be worn outside the lead apron near the neck to accurately measure the dose of radiation the worker is exposed to, as the lead apron shields the body from radiation.

Question 8

The length of the exposure cord of a mobile X-ray unit should be at least:&#10;A) 8 feet&#10;B) 6 feet&#10;C) 4 feet&#10;D) 2 feet

Accepted Answer

The length of the exposure cord of a mobile X-ray unit should be at least 6 feet to ensure the operator can maintain a safe distance from the radiation source during exposure.

Question 9

The law of Bergoni&#233; and Tribondeau implies that radiosensitivity is greatest in:&#10;A) cells that are rapidly dividing&#10;B) cells that are highly differentiated&#10;C) cells that divide slowly over time&#10;D) cells that make up the nervous system

Accepted Answer

The law of Bergonié and Tribondeau states that cells are more radiosensitive if they are rapidly dividing, less differentiated, and have a longer mitotic future. Therefore, cells that are rapidly dividing are most sensitive to radiation.

Question 10

Which of the following is the most effective means of protecting the radiographer from exposure to radiation?&#10;A) Minimize time&#10;B) Increase distance&#10;C) Wearing a lead apron&#10;D) All of the above

Accepted Answer

The answer of Which of the following is the most...

Deck 10: Radiation Safety and Protective Measures