Radiation Units/Monitoring Flashcards
An ionization chamber connected to an electrometer is a device that can measure:
a. tiny electric currents with high precision and accuracy.
b. electromagnetic force.
c. potential difference.
d. voltage in an x-ray machine circuit.
A
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.
high-speed electrons
beta particles
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
In therapeutic radiology what SI units are now routinely used to specify absorbed dose?
Gray and centigray
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 of the above
Some of the advantages of the optically stimulated luminescence (OSL) dosimeter are
1. can be used for up to 1 year.
2. lightweight, durable, and easy to carry.
3. integrated, self-contained, preloaded packet.
1, 2, and 3
The whole-body TEDE regulatory limit for exposed personnel is _____________ and ______________ for the general public.
0.05 Sv; 0.001 Sv
What types of ionizing radiation produce virtually the same biologic effect in body tissue for equal absorbed doses?
X-rays, beta particles, and gamma rays
Whenever the letter “M” appears under the current monitoring period or in the cumulative columns of a personnel monitoring report, it signifies that a (an)
equivalent dose below the minimum measurable radiation quantity was recorded during that time.
radiation dose to which occupationally exposed persons could be subjected without any apparent harmful acute effects, such as erythema of the skin.
Tolerance dose
The basic unit of electrical charge
Coulomb
SI unit of electrical current
Ampere
Used to express how energy in transferred from a beam of radiation to air
Air kerma
The quantity of energy delivered to a patient by the x-ray beam
dose area product
What was used as the first measure of exposure for ionizing radiation?
Skin erythema
What is the unit of collective effective dose (ColEfD)?
Person-sievert
What is the SI radiation unit coulomb per kilogram used to specify?
Radiation exposure in air only
Which of the following radiation quantities accounts for some biologic tissues being more sensitive to radiation damage than other tissues?
Effective dose
When laser light is incident on the sensing material in an OSL dosimeter, the material:
A. Becomes luminescent in proportion to the amount of radiation exposure received B. Fluoresces in proportion to the amount of radiation exposure received and then emits beta particles
C. Phosphoresces in proportion to the amount of radiation exposure received and then darkens
D. Turns ice blue in color and fluoresces in proportion to the amount of radiation exposure received
A
Which of the following chemical compounds functions as the sensing material in a thermoluminescent ring dosimeter?
Lithium fluoride
During routine radiographic procedures, when a protective apron is not being worn, the primary personnel dosimeter should be attached to the clothing on the front of the body at:
Collar level to approximate the location of maximal radiation dose to the thyroid and the head and neck
When a radiologic procedure requires the hands of a radiation worker to be near the primary beam, the equivalent dose to the hands of that individual may be determined through the use of:
A TLD ring dosimeter worn on the hand of the radiation worker
Which of the following instruments is used to calibrate radiographic and fluoroscopic x-ray equipment?
Ionization chamber with electrometer
Which of the following instruments should be used to locate a lost radioactive source or detect low-level radioactive contamination?
GM survey meter
Which of the following instruments should be used in an x-ray installation to measure the fluoroscopic scatter radiation exposure rate?
cutie pie
Required when workers are likely to receive ___ or more of the annual occupational EfD limit in any single year
10%
