RAD BIO QUIZ 1 Flashcards
Which unit of measurement is standard for use?
SI-Systeme International
Amount of radiation in the primary beam. (x-ray tube output)
Exposure
How do we measure exposure?
Coulomb per Kilogram
Energy per unit mass absorbed by an irradiated object.
Absorbed dose
What is the measurment for absorbed dose?
Gray(Gy). 1J/kg
1 Joule = 1 Gy
What is the Dose equivalent?
Absorbed dose x radiation weighting factor
What is the radiation weighting factors?
Xray, Gamma, Beta and positron=1
Proton=2
Alpha particles=20
The sum of the equivalent doses for all irradiated tissues.
Effective Dose
What considers the type of radiation and the sensitivity of the tissues?
Effective Dose
Absorbed dose x radiation weighting factor x tissue weighting factor
Effective Dose
Tissue Weighting Factors:
Gonads- .20
Red Bone Marrow- .12
Colon- .12
Liver- .05
Skin- 0.01
In which unit is Effective Dose measured?
Siverts (Sv)
Kinetic energy of the primary beam
AIR KERMA.
only used for photons- (XRAY AND GAMMA)
What does KERMA stand for?
Kinetic Energy Released in MAtter
How is Air Kerma measured?
Gray (Gy)
Takes into account the area being irradiated.
Dose Area Product (DAP)
How is DAP measured?
DAP meter
What is the formula for DAP?
absorbed dose x irradiated (Collimated Area)
The time required for radioactivity rate to reduce to 1/2 its original measurement. Specific to radioisotope and constant.
Half-Life
Sum of all absorbed doses in an exam
ex: 3 view lumbar
Integral Dose
What is considered Background Radiation?
Natural (radon)
Manmade (consumer products) highest in tightly sealed structures such as granite or marble
How much background radiation on average does a person receive per year?
3 mSv
What are the types of Dosimeters?
OSLD
TLD
FILM BADGE
POCKET/ ION CHAMBER
Which dosimeter has dose released by light?
OSL- optically stimulated luminescence dosimeter
In which dosimeter is the dose released by heat?
TLD- thermoluminescent
Which dosimeter has a small piece of film with a foil filter?
Film badge
Which dosimeter can determine what type of radiation received?
Film badge
Which dosimeter provides real-time dose readings using an anode pin or plate?
Pocket/ ion chamber
What is the occupational dose limit per year?
50 msv
Which modality receives the highest occupational dose per year?
Fluoroscopy/ IR
What is the public dose limit?
1mSv
What is the fetal dose limit per month?
0.5mSv
What is the dose limit for the lens of your eye?
150 mSv
What is the dose limit for “everything else” ex: elbow, knee cap
500 mSv
The amount of energy deposited in tissue per unit path length of radiations travel
Linear Energy Transfer (LET)
What has a high LET?
Alpha particles
what has a low LET?
XRAYS
GAMMA (LOWEST)
If the energy deposited into the tissue is more concentrated and therefore harmful, is this a high or Low LET?
HIGH
Relative Biological Effectiveness (RBE)
Comparison of different types of radiation.
ex: x-ray and alpha particles
If one type of radiation can cause the same effect as other with a lower amount, does it have a higher or lower RBE?
Higher RBE
Graphic representation of the degree of a biological response to increasing doses of ionizing radiation.
Radiation Response Curves
How many millisieverts is in one Sv?
1000
