Exercise 4 Flashcards
(31 cards)
What publication recommends limits of exposure to ionizing radiation?
NCRP #116
Why do film badge holders have filters inside?
To determine radiation energies
Which publication contains regulations for using X-rays up to 50MeV?
NCRP #102
A “radiation area” sign must be visible in areas where the exposure rate exceeds how much? For a high radiation area sign?
.05 mSv/hr (5mrem/hr) for radiation area and 100mrem/hr for high radiation
What is rem?
Radiation Equivalent Man
Expresses equivalent dose. It is absorbed dose times a weighting factor for the type of radiation
Personnel monitoring shall be preformed if there is a possibility of exceeding how many millisievert (rem) per year?
5.0 mSv (.25rem)
What is covered in NCRP 102?
Equipment design and use, personnel monitoring, and radiation survey procedures.
What is a roentgen?
A measurement of the ionization of air produced by x or gamma radiation.
Which of the following is required on mobile fluoroscopy units? Why?
A) VCR capabilities
B) Image intensification
C) T.V. Monitoring
D) Solid state circuitry
B) Image intensification
Brightens the tim age about 4,000 times which allows less radiation exposure to the patient
What causes characteristic radiation?
Absent electrons in an ionized atom
How many milliroentgen are in one roentgen?
1000
What are two general types of radiation detection devices?
Field survey (ionization chambers and GM counters) used to determine exposure rates and detection of radiation
Personnel monitoring (film badges and TLDs) measure dose (dosimetry).
What is the diagnostic xray energy range?
Between 25-140 keV
What unit of measurement is equal to 1 joule per kilogram?
Gray
What is used in a optically stimulated luminescence dosimeter to detect radiation?
Aluminum oxide
What government agency is responsible for governing the use of radiation? How?
Food and Drug Administration
Conducts inspections of institutions to determine if the radiographic equipment meets the standards set by the NCRP and NCR
What type of radiation is alpha and beta? Why?
Particulate radiation because they have mass
What is the density of a film badge compared to in order to determine the exposure of a worker?
Density standard
What is the least expensive radiation monitoring device?
Film badges
What is a cutie pie?
A radiation survey instrument designed to detect x, gamma, and beta radiation. Looks like a space gun and is commonly found in the bey clear medicine department.
What is the cumulative effective dose limit for a 25 year old radiation worker?
250mSv (25 rem) NCRP 116 recommends that an individual’s rem bank cannot exceed her/his age
What increases the probability of photoelectric absorption occurring?
Decrees in kVp and increase in the atomic number of the material
How accurate are optically stimulated luminescence dosimeters? Thermoluminescent dosimeters? Film badges?
OSL dosimeter to 1mrem
TLD to 5mrem
Film badge to 10mrem
What do radiation monitoring instruments depend on?
Ionization
