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1.1 Basic Physics |
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1 |
In the Compton effect: |
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(a) |
There is interaction between a photon and a free electron.
John's answer
TRUE |
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(b) |
The larger the angle through which the photon is scattered, the more energy it loses.
John's answer
TRUE |
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(c) |
The wavelength change produced depends upon the scattering material.
John's answer
FALSE |
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(d) |
High energy radiation is scattered more than lower energy radiation.
John's answer
Depends what you mean by "scattered more". |
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(e) |
The amount of scattering that occurs depends on the electron density of the scattering material.
John's answer
TRUE |
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1.2 Radiation Hazards and Dosimetry |
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2 |
Concerning radiation dose: |
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(a) |
PA chest x-ray effective dose is approximately 0.02
mSv.
John's answer
TRUE |
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(b) |
Annual effective dose limit for members of the
public is 5 mSv.
John's answer
FALSE (1 mSv) |
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(c) |
Average annual dose in the UK from natural
background radiation is 0.1 Sv.
John's answer
FALSE (2.3 mSv) |
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(d) |
The average annual effective dose to the UK
population from medical exposure is 3 mSv.
John's answer
FALSE (0.37 mSv) |
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(e) |
Effective dose to patients having a radionuclide
bone scan with 600 MBq technetium-99m is approximately 4 mSv.
John's answer
TRUE |
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2.1 General Radiation Protection |
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3 |
In diagnostic radiology, the following values are typical: |
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(a) |
5 mSv is the annual effective dose limit for classified staff.
John's answer
FALSE (20 mSv) |
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(b) |
1 mGy for skin dose to the patient in chest radiography.
John's answer
FALSE (0.2mGy for PA chest) |
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(c) |
2 mm lead equivalence for a lead rubber apron.
John's answer
FALSE (0.35 mm or 0.25 mm) |
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(d) |
25 mGy per minute for entrance dose rate to patient during abdominal fluoroscopy.
John's answer
TRUE |
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(e) |
4 GBq of iodine-131 for a diagnostic thyroid scan.
John's answer
FALSE (0.2 MBq for scan) |
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3.1 Ionising Radiations Regulations 1999 |
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4 |
An employee must become a classified worker if |
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(a) |
they work more than three sessions per week with ionising radiation.
John's answer
FALSE |
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(b) |
three tenths of relevant dose limit is exceeded.
John's answer
TRUE |
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(c) |
they are likely to receive a whole body dose greater than 6 mSv annually.
John's answer
TRUE |
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(d) |
the dose to their hands is likely to exceed 150 mSv annually.
John's answer
TRUE |
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(e) |
they become pregnant.
John's answer
FALSE |
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3.2 & 3.3
Ionising Radiation (Medical Exposure) Regulations 2000 and Other Relevant Legislation |
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5 |
Regarding The Ionising Radiation (Medical Exposure) Regulations 2000 [IR(ME)R]: |
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(a) |
Overall responsibility for keeping dose to the patient as low as reasonably practicable rests with the practitioner.
John's answer
?FALSE? - practitioner responsible for his bits, operators responsible for their bits. |
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(b) |
The practitioner is the only person entitled to authorise an x-ray exposure.
John's answer
FALSE - operator can authorise in line with practitioner's guidelines. |
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(c) |
Only doctors and dentists are permitted to request an x-ray.
John's answer
FALSE |
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(d) |
The person performing quality control tests on an isotope calibrator must have training as required by IR(ME)R.
John's answer
TRUE |
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(e) |
The enforcing authority for IR(ME)R is the Health and Safety Executive.
John's answer
FALSE (DoH) |
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4.1 Diagnostic Radiology |
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6 |
Radiological image unsharpness increases |
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(a) |
if shorter exposure times are used.
John's answer
FALSE |
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(b) |
as the object to film distance increases.
John's answer
TRUE |
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(c) |
as the target angle decreases.
John's answer
FALSE |
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(d) |
if a grid is used.
John's answer
FALSE |
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(e) |
as the focal spot size increases.
John's answer
TRUE |
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4.2 Fluoroscopy and Fluorography |
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7 |
In automatic mode fluoroscopy, the patient entrance surface dose rate |
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(a) |
usually increases with image intensifier field size.
John's answer
FALSE |
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(b) |
depends on the added filtration.
John's answer
TRUE |
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(c) |
is independent of the kV-mA characteristic used.
John's answer
FALSE |
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(d) |
doubles if the patient-intensifier face distance is halved.
John's answer
FALSE |
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(e) |
should be less than 50 mGym-1.
John's answer
FALSE - milligray per metre is not a unit of dose rate |
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4.3 Computed Tomography |
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8 |
Regarding computed tomography: |
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(a) |
A CT number of 0 is assigned to water.
John's answer
TRUE |
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(b) |
Image quality is limited by electronic noise. John's answer
FALSE |
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(c) |
Axial image resolution is improved with reduction in slice width.John's answer
TRUE |
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(d) |
An unfiltered x-ray beam is used.
John's answer
FALSE |
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(e) |
The typical effective dose for a CT head scan is 10 mSv.
John's answer
FALSE (2.3 mSv) |
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4.4 Patient Dosimetry |
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9 |
The dose to a patient may be reduced by using |
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(a) |
a grid.
John's answer
FALSE |
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(b) |
collimators.
John's answer
TRUE |
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(c) |
additional copper filters.
John's answer
TRUE |
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(d) |
a high tube voltage.
John's answer
TRUE |
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(e) |
a small focal spot.
John's answer
FALSE |
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4.5 Radionuclide Radiology |
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10 |
Concerning radiopharmaceuticals: |
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(a) |
The ideal radiopharmaceutical should have as short a physical halflife as possible.
John's answer
FALSE (short, but not too short.)
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(b) |
The ideal imaging radiopharmaceutical should emit only gamma radiation.
John's answer
TRUE |
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(c) |
The gamma radiation emitted contributes a larger part of the radiation dose to the patient than any accompanying beta radiation.
John's answer
FALSE (?)
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(d) |
The effective half-life is longer than the biological half-life.
John's answer
FALSE |
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(e) |
The labelling isotope should remain attached to the tracer material throughout the examination.
John's answer
TRUE |
