Final test 4-7 Flashcards
Who was the first American radiation worker to die from radiation-induced cancer in October of 1904?
Clarence Madison Dally
Which of the following are early tissue reactions of ionizing radiation that were experienced by early radiation workers?
1. Diffuse redness of skin
2. Blood disorders
3. Organ atrophy
4. Intestinal disorders
1,2, and 4
0.2 Gy equals
200 mGy
The total kinetic energy released in a unit mass (kilogram) of air and expressed in metric units of joules per kilogram is
air kerma
Which of the following is essentially the sum total of air kerma over the exposed area of the patient’s body surface?
Dose area product
The whole-body TEDE regulatory limit for exposed personnel is _____________ and ______________ for the general public.
0.05Sv; 0.0001 Sv
As the intensity of x-ray exposure of the air volume increases, the number of electron–ion pairs produced
also increases
What do radiation weighting factors take into consideration?
-the overall risk of exposure to humans from ionizing radiation
-both the internal and external dose measurments
-the fact that some types of radiation are more efficient at causing biologic damage than other types of radiation for a given dose
1 gray equals
100 cGy
In the SI system, an energy absorption of 1 J/kg of matter in the irradiated object equals which of the following?
1 Gy
Cataract formation, fibrosis, reduced fertility, and sterility are classified as
late tissue reactions of ionizing radiation
Which of the following types of ionizing radiation produce virtually the same biologic effect in body tissue for equal absorbed doses?
X-rays, beta particles, and gamma rays
What theory relates the ionization produced in a small cavity within an irradiated medium or object to the energy absorbed in that medium as a result of its radiation exposure?
Bragg-Gray
If 400 people receive an average effective dose of 0.25 Sv, what is the collective effective dose?
100 person-sv
For x-ray and gamma ray photons with energies up to 3 million electron volts (MeV), which of the following radiation quantities may be defined as the measure of the total electrical charge of one sign, either all pluses or all minuses, per unit mass that these two types of radiation generate in dry air (i.e., nonhumid) at standard temperature and pressure (760 mm Hg or 1 atmosphere at sea level and 22° C)?
Exposure
Which of the following formulas is used to calculate effective dose?
EfD = D × WR × WT
Alpha particles have a radiation weighting factor (WR) that is numerically equal to
20
Which of the following units of measure are not SI units?
Roentgens and rads and rems
How is dose area product usually specified?
In units of mGy-cm2
What instrument can be calibrated to read air kerma?
Standard, or free-air, ionization chamber
Which of the following is the SI unit of electrical current?
Ampere
Which of the following is the SI unit of electrical current?
high-speed electrons
Among physicians, cancer deaths attributed to x-ray exposure were reported as early as
1910
Among physicians, cancer deaths attributed to x-ray exposure were reported as early as
Gray and centigray
Who discovered x-rays on November 8, 1895?
Wilhelm Conrad Roentgen
Three different filters are incorporated into the detector packet of the optically stimulated luminescence dosimeter. Of what are these filters made?
Aluminum, tin, and copper
What is the maximum period of time that a thermoluminescent ring dosimeter (TLD) may be worn as a personnel device?
3 months
What do optically stimulated luminescence dosimeters, thermoluminescent ring dosimeters, and personnel direct ion storage dosimeters have in common?
These devices are all used for personnel monitoring.
Which of the following instruments is called a cutie pie?
Ionization chamber-type survey meter
Which of the following instruments generally has a check source of a weak, long-lived radioisotope located on one side of its external surface to verify its constancy daily?
Geiger-Műller survey meter
Which of the following devices contains an aluminum oxide detector?
Optically stimulated luminescence dosimeter
When the sensing material contained in the thermoluminescent ring dosimeter is irradiated, which of the following occurs?
Some of the electrons in the crystalline lattice structure of the LiF molecule absorb energy and are excited to higher energy levels or bands.
Because of the OSL dosimeter’s sensitivity down to as low as 10 µSv for x-ray and gamma ray photons in the energy range 5 keV to 40 MeV, it is an excellent and practical monitoring device for
employees working in low-radiation environments and for pregnant workers.
The effective atomic number (Zeff) of lithium fluoride (LiF) is equal to
8.2
Which of the following are advantages of the personnel direct ion storage dosimeter?
1. Instant access to reports
2. No waiting time for mailing dosimeters
3. Lightweight and durable
4. Can be dropped or scratched with little chance of harm to the device
All options
How is the readout for a personnel direct ion storage dosimeter obtained?
Through a physical connecting device such as a universal serial bus (USB) or via wireless connection
Which of the following are disadvantages of the TLD ring dosimeter?
Thermoluminescence readings will be lost if not carefully recorded.
The readout process destroys information stored in the TLD ring dosimeter, thus preventing the “read” from serving as a permanent legal record of exposure.
Calibrated dosimeters must be prepared before-hand and read with each group of TLDs as they are processed.
Which component(s) of the Geiger-Muller survey meter alerts the operator to the presence of ionizing radiation?
An audio amplifier and speaker
Which of the following is not a requirement that radiation survey instruments must meet?
Correct!
They must all be equally sensitive in the detection of all types of ionizing radiation.
Medical physicists use ionization chambers, connected to electrometers to perform the annual standard measurements required by state, federal, and health care accreditation organizations for radiographic and fluoroscopic devices. These annual measurements include
1. x-ray output in Gy or mGy.
2. fluoroscopic radiation entrance rates in mSv/min or R/min.
3. kVp setting accuracy.
4. exposure time exactness.
5. half-value layers, or beam quality.
All options