Challenge #2

The effective dose limit for a fetus for the entire gestational period is: A. 5 mSv B. 0.5 mSv C. 0.05 mSv D. 50 mSv

A. 5 mSv

A radiation dose that if received by the entire population would cause the same genetic injury as the total of doses received by the members actually being exposed is called: A. genetically significant dose B. doubling dose C. mean marrow dose D. genetic dose

A. Genetically Significant Dose *This describes the GSD, or genetically significant dose(not called genetic dose). The doubling dose is the amount of radiation that causes the number mutations in a population to double. Mean marrow dose is the average dose to active bone marrow as an indicator of somatic effects on population.

When radiation strikes DNA, which of the following occurs? A. direct effect B. law of Bergonie and Tribondeau C. target theory D. indirect effect

A. direct effect *indirect effect occurs when radiation strikes the cytoplasm of the cell. Target theory states there is a master molecule that governs cellular activities that is DNA.

Effective Dose limit (EfD) A. is the level of radiation that an organism can receive and probably sustain no appreciable effects. B. is a safe level of radiation that can be received with no effects C. Should be absorbed annually to maintain proper immunity to radiation. D. Is 500mSv per year for the general public

A. is the level of radiation that an organism can receive and probably sustain no appreciable effects.

The photoelectric effect: A. results in absorption of the incident photon B. results in absorption of the incident electron C. produces contrast fog on the radiographic image D. is the same as brems radiation

A. results in absorption of the incident photon

A lead apron of at least what thickness should be worn while being exposed to scatter radiation? A. 0.25 mm Pb equivalent B. 0.5 mm Pb equivalent C. 0.5 mm Al equivalent D. 0.25 mm Al equivalent

B. .5 mm Pb equivalent *shielding of lead (Pb) equivalent, not aluminum (Al) equivalent, is used to protect from scatter radiation. The requirement for a lead apron is at least .25mm Pb equivalent; it should be .5mm Pb equivalent.

Use of a thyroid shield of at least what thickness should be used for fluoroscopy? A. 0.10 mm Pb equivalent B. 0.5 mm PB equivalent C. 0.5 mm Al equivalent D. 0.10 mm Al equivalent

B. 0.5 mm Pb equivalent *the requirement for a thyroid shield if during fluoroscopy is .5mm lead.

Optically stimulated luminescence (OSL) dosimeters provide readings as low as: A. 1 uSV B. 10 uSv C. 50 uSv D. 100 uSv

B. 10uSv *OSL dosimeters are very sensitive. This feature along with their wide dynamic range, greater accuracy and long-term stability makes them ideal for personnel monitoring.

Which of the following states that the radiosensitivity of cells is directly proportional to their reproductive activity and inversely proportional to their degree of differentiation? A. inverse square law B. law of Bergonie and Tribondeau C. target theroy D. ohm's law

B. Law of Bergonie and Tribondeau *cells such as epithelial, ovarian and sperm cells.

Medical xrays are an example of: A. natural background radiation B. artificially produced radiation C. nonionizing radiation D. ionizing natural background radiation

B. artificially produced radiation *this is human produced radiation

The amount of radiation that causes the number of genetic mutations in a population to double is called the: A. threshold dose B. doubling dose C. mutagenic dose D. genetic dose

B. doubling dose

Radiation with a high LET: A. has low ionization B. is highly ionizing C. carries a low quality factor D. equates with a low RBE

B. is highly ionizing *high LET radiation is depositing a lot of energy in the tissues, causing much ionization.

Thermoluminescent dosimeters use what type of crystals to record dose? A. dilithium crystals B. lithium fluoride C. flux capacitors D. bromide crystals

B. lithium fluoride *lithium fluoride crystals, which release visible light when heated, are used to record dose in TLD.

TLD are heated and release what type of crystals to record dose? A. laser B. visible light C. xrays D. gamma rays

B. visible light *TLDs are heated and released visible light energy to indicate dose. This energy is read by a photomultiplier tube.

OSl dosimeters may be worn for: A. 1 month B. 1 week C. 3 months D. 1 year

C. 3 months *OSL dosimeters can be worn for up to a quarter, although in many cases they may be changed monthly.

The annual effective dose limit for radiographers is: A. 10 mSv B. 100 mSv C. 50 mSv D. 100 mSv

C. 50 mSv

Primary protective barriers must extend to a height of: A. 5 ft B. 6 ft C. 7 ft D. 10 ft

C. 7ft *primary protective barriers in the wall must extend to a height of at least 7ft because this height is taller than most people.

The amount of radiation deposited per unit length of tissue traversed by incoming photons is called: A. tissue exposure B. linear deposition of energy C. linear energy transfer D. effective dose limit

C. Linear Energy Transfer * more energy is deposited by particulate forms of radiation than by waveforms of radiation.

Gray^t multiplied by a radiation weighting factor equals: A. air kerma B. Becquerel C. Sievert D. Gray^a

C. Sievert

The recording material in an OSL dosimeter is: A. dilithum B. lithium fluoride C. aluminum oxide D. silver halide

C. aluminum oxide *the recording material in an OSL dosimeter is aluminum oxide, which is then scanned by a laser beam. Film badges use film as the recording material; TLD use lithium fluoride.

The most commonly used gonadal shield is the: A. shadow shield B. collimatore C. contact shield D. filter

C. contact shield *the flat contact shield, which consists of a piece of lead placed over the gonads, is the most commonly used. It may be as simple as a lead apron properly placed. The shadow shield, which is suspended from the xray housing and does not come in contact with the patient, is used when sterile technique is required.

Filters made of aluminum and copper are placed in the film badge to measure xray: A. quantity B. source C. energy D. type

C. energy *filters made of aluminum and copper are placed in the film badge to measure the xray energy striking the film badge. This is a measure of the beams quality, not quantity. Film badges do not measure the source or type of xray beam.

The energy stored in a OSL dosimeter is released when the dosimeter is exposed to: A. heat B. white light C. laser D. ultrasound

C. laser *the energy stored in an OSL dosimeter is released by exposure t a laser. The energy stored in a TLD is released by heat.

Radiation protection is based on which dose-response relationship? A. linear-threshold B. nonlinear-nonthreshold C. linear-nonthreshold D. nonlinear-threshold

C. linear-nonthreshold *it is assumed that for every dose of radiation, a response occurs in the atoms of the person being irradiated.

Secondary protective barriers must extend to a height of: A. 5 ft B. 6 ft C. the ceiling D. 10 ft

C. the ceiling *the secondary protective barrier extends from when the primary protective barrier ends to the ceiling with a 1/2 inch overlap.

The Bucky slot cover must be at least: A. 0.5 mm Pb equivalent B. 0.25 mm Al equivalent C. 0.10 mm Pb equivalent D. 0.25 mm Pb equivalent

D. 0.25 mm Pb equivalent

The protective curtain banging from the fluoroscopy tower must be at least: A. 0.5 mm Pb equivalent B. 0.25 mm Al equivalent C. 0.10 mm Pb equivalent D. 0.25 mm Pb equivalent

D. 0.25 mm Pb equivalent *The protective curtain hanging from the fluoroscopy tower must be at least .25 mm Pb.

How thick are primary protective barriers? A. 1/32" lead equivalent B. 1/16" aluminum equivalent C. 1/32" aluminum equivalent D. 1/16" lead equivalent

D. 1/16 lead equivalent *primary protective barriers consist of 1/16 inch lead equivalent. Secondary protective barriers consist of 1/32 inch lead equivalent

Cataractogenesis, life span shortening, embryologic effects, and carcinogenesis are examples of: A. short-term somatic effects B. genetic effects C. acute radiation syndrome D. long-term somatic effects

D. Long term Somatic Effects *all are examples of radiation effects on teh individual being exposed.

The SI units of equivalent dose, activity, air kerma, and absorbed dose: A. roentgen, rad, rem curie B. rad, coulomb per kilogram, curie, bacquerel C. rem, curie, roentgen, rad D. sievert, becquerel, gray^a, gray^t

D. Sievert, Becquerel, gray^, gray^t

Compton interaction: A. increases contrast in the radiographic image B. results in scattering of the incident electrons C. decreases recorded detail in the radiographic image D. decreases contrast in the radiographic image.

D. decreases contrast in the radiographic image

For optimal radiation protection, what type of exposure technique should be used? A. low kVp, high mAs B. small focal spot C. all manual technique D. high kVp, low mAs

D. high kVp, low mAs *low mAs reduced the amount of radiation striking the patient. Choosing the optimum kVp for the part being radiographed increases th equality of the xray beam. Low kVp, high mAs, would result in the opposite.

Which of the following causes about 95% of the cellular response to radiation? A. direct effect B. law of Bergonie and Tribondeau C. target theory D. indirect effect

D. indirect effect * because the cellular cytoplasm is substantially larger

The average dose to active bone marrow as an indicator of somatic effects on a population is called: A. doubling dose B. bone dose C. GSD D. mean marrow dose

D. mean marrow dose *This is the definition of mean marrow dose (MMD). It is not called the bone dose. The doubling dose is the amount of radiation that causes the number of mutations in the population to double. The GSD is the genetically significant dose

Film badges are changed: A. quarterly B. weekly C. yearly D. monthly

D. monthly *a film badge should not be worn longer than 1 month, at which time a film badge report with readings is returned to the institution.

OSL dosimeters may be scanned and reanalyzed: A. only once B. monthly C. five times D. an unlimited number of times

D. unlimited number of times *one of the key advantages of OSL dosimeters is the capability of reanalysis for confirmation of dose, which is especially important if a dose is in question.