Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
16 Cards in this Set
- Front
- Back
|
1 roentgen is equal to |
2.58 x 10^-4 C/kg |
|
|
Coulomb |
Basic unit of electrical charge Quantity of electrical charge flowing past a point in a circuit in 1 second when current is 1 ampere |
|
|
Ampere |
SI unit for electrical current |
|
|
Air kerma |
Radiation concentration transferred to point, which may be @ surface of patient's body J/kg |
|
|
Absorbed Dose (D) |
Amount of energy per unit mass absorbed by irradiated object - Cause of biologic damage |
|
|
Equivalent dose |
Product of average absorbed dose in tissue or organ |
|
|
Electromagnetic radiation |
amount of energy transferred to electrons by ionizing radiation |
|
|
Ionizing radiation |
produces ions (positively and negatively charged particles) when passing through matter |
|
|
Consequences of Ionization |
Unstable atoms Free electrons Low NRG photons Free radicals Detrimental biologic molecules injury to cell |
|
|
Important Properties of X-ray |
Invisible varying penetration NOT deflected NOT focused w/ lens straight lines fluorescence darken film heterogenous |
|
|
Exposure |
Amount of ionizing radiation produced in AIR when ionizing radiation is present C/kg or mR (milliroentgens) |
|
|
Absorbed Dose |
Amount of energy that is deposited in material per unit mass Gray or milliGray (1 Gray = 100 rads) Green dollar to red pennies |
|
|
Effective Dose |
Measure of general harm in humans |
|
|
Maintaining ALARA |
Written policy Management keeps all exposure ALARA based RSO Audits |
|
|
CT in children |
Boys: 3 to 4 times the risk in 1st year, 20 to 50 yrs Girls: 6 to 8 times the risk in 1st year, 20 to 50 yrs |
|
|
CT regulations |
Annual education minimum qualifications for medical physicists Document CT doses Manage CT protocols |
