Basic Principles (3) Flashcards
What is exposed during a radiograph?
The article being tested and the film.
Factors that determine exposure time include:
- Energy and intensity of radiation
- Thickness and density of test article
- Source to film distance
- Independent film variables (film speed, required film density etc.)
Techniques used to produce radiographs using x-rays vs gamma rays are _____.
similar, main differences being the source of radiation and the ability/non-ability to control the energy and intensity of the beam.
List Exposure Factors
- Source-to-film distance
- alignment of beam
- geometrical imaging factors
- type of film
Differences between x-ray and gamma ray equipment
Generation: x-ray = electric, gamma = disintegration
Control of energy: x-ray = adjust kV, gamma = characteristic of isotope
Control of intensity: x-ray = adjust mA, gamma = characteristic of isotope
The radiographers main objective should be obtaining a radiographic image of the specimen with the greatest amount of ______.
Detail
Always use an energy that is as ____ as _____.
as Low as Practical
Why do we desire lower intensities of radiation for radiographs?
lower energies produce radiographs of higher definition and contrast.
If we can’t control energy and intensity of gamma radiation, what can we do to improve a radiograph?
slight adjustments to controllable variables:
- film selection
- source to film distance
- use of film screens
Gamma rays produce somewhat _____ radiation.
Harder radiation.
- images of slightly lesser resolution