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Front 1

In film radiology, penetrometers are usually placed:

Back 1

On the source side of the test object

Front 2

Cobalt-60 used in nondestructive testing emits:

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Gamma rays

Front 3

A densitometer is:

Back 3

An instrument for measuring the density of a material

Front 4

The two most common causes for excessively high-density radiographs are:

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Over exposure and overdevelopment

Front 5

The time required for one half of the atoms in a particular sample of radioactive material to disintegrate is called:

Back 5

A half-life

Front 6

What does the term R/hr refer to when speaking of intensity?

Back 6

Roentgens per hour

Front 7

The ability to detect a small discontinuity or flaw is called:

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Radiographic sensitivity

Front 8

Movement, geometry, and screen contact are three factors that affect:

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Radiographic unsharpness

Front 9

The difference between the densities of two areas of a radiograph is called:

Back 9

Radiographic contrast

Front 10

Upon completing an x-ray exposure and turning the equipment off:

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Personnel should enter the exposure area without fear of radiation exposure

Front 11

The most widely used unit of measurement for measuring the rate at which the output of a gamma-ray source decays is the:

Back 11

Curie

Front 12

Exposure to x-rays or gamma rays:

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May have a cumulative effect which must be considered when monitoring for maximum permissible dose.

Front 13

Which dose would be dangerous, if not fatal, if applied to the entire body in a short period of time?

Back 13

200 - 800 R

Front 14

When doing gamma-ray radiography with high-intensity emitters, the sources are best handled:

Back 14

by remote handling equipment

Front 15

If a film is placed in a developer solution and allowed to develop without any agitation:

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there will be a tendency for each area of the film to affect the development of the areas immediately below it.

Front 16

The selection of the proper type of film to be used for the x-ray examination of a particular part depends on:

Back 16

the thickness of the part, the material of the specimen and the voltage range of the available x-ray machine

Front 17

When radiographing a part which contains a large crack, the crack will appear on the radiograph as:

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A dark, intermittent or continuous line

Front 18

A cobalt-60 source has a half-life of:

Back 18

5.3 years

Front 19

Lead foil in direct contact with x-ray film:

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intensifies the primary radiation more than the scatter radiation

Front 20

In order to decrease geometric unsharpness:

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radiation should proceed from as small a focal spot as other considerations will allow

Front 21

Scattered radiation caused by any material, such as a wall or floor, on the film side of the specimen is referred to as:

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backscattered radiation

Front 22

Any of the body tissues may be injured by excessive exposure to x-ray or gamma-rays but particularly sensitive are:

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blood, lens of the eye and internal organs

Front 23

A general rule used to define the amount of radiation exposure that is excessive is:

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Any unnecessary exposure to radiation is excessive

Front 24

Excessive exposure of film to light prior to development of the film will most likely result in:

Back 24

a foggy film

Front 25

White crescent-shaped marks on an exposed x-ray film are most likely cause by:

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crimping film before exposure

Front 26

Reticulation resulting in a puckered or net-like film surface is probably caused by:

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sudden extreme temperature change while processing

Front 27

Frilling or loosening of the emulsion from the base of the film is most likely caused by:

Back 27

Warm or exhausted fixer solution

Front 28

If an exposure time of 60 seconds was necessary using a 4-foot source-to-film distance for a particular exposure, what time would be necessary if a 2-foot source-to-film distance is used and all other variables remain the same?

Back 28

15 seconds (at half the distance, exposure time is one fourth according to the inverse square law) 60 x .25 = 15

Front 29

One of the general rules concerning the application of geometric principles of shadow formation to radiography is:

Back 29

the distance between the anode and the material examined should always be as great as possible. (the optimum distance depends on specimen size, thickness, film speed, source strength, etc)

Front 30

As a check on the adequacy of the radiographic technique, it is customary to place a standard test piece on the source side of the specimen. The standard test piece is called a:

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penetrometer (the use of a particular penetrometer are determined by the code procedure

Front 31

A penetrometer is used to indicate:

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the quality of the radiographic technique

Front 32

The three main steps in processing a radiograph are:

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developing, fixation, and washing

Front 33

Lead foil screens are used in radiography:

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to improve the quality of the radiograph by preferentially reducing the effect of scatter radiation and to reduce the exposure time

Front 34

When the minute silver grains on which the x-ray film image is formed group together in relatively large masses, they produce a visual impression called:

Back 34

graininess

Front 35

To prevent excessive backscatter from reaching a radiograph film, one should:

Back 35

back the cassette with a sheet of lead, the thickness needed depending on the radiation quality

Front 36

Static marks, which are black tree-like or circular marks on a radiograph, are often caused by:

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improper film handling techniques

Front 37

The purpose of agitating an x-ray film during development is to:

Back 37

renew the developer at the surface of the film and prevent/reduce streaking

Front 38

When manually processing films, the purpose for sharply tapping hangers two or three times after the films have been lowered into the developer is to:

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dislodge any air bubbles clinging to emulsion

Front 39

The activity of the developer solution is maintained stable by:

Back 39

addition of replenisher

Front 40

The purpose of fixation is:

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to remove all the undeveloped silver salts of the emulsion, to leave the developed silver as a permanent image and to harden the gelatin

Front 41

For best results when manually processing film, solutions should be maintained within a temperature range of:

Back 41

65 - 75 degrees F

Front 42

Water spots on films can be minimized by:

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immersing wet film for one or two minutes in a wetting agent solution.

Front 43

This is the filament end where the electrons flow. Unwanted inclusions in a part will appear on a radiograph as:

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either a dark or light spot or area depending on the relative absorption ratio of the part material and the inclusion material.

Front 44

The radiation quality of a gamma-ray source is:

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determined by the isotope involved

Front 45

The most common material used to provide protection against x-rays is:

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lead

Front 46

A curie is the equivalent of:

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1,000 millicuries (one thousand milli - (one thousandth) curies equal one curie

Front 47

With a given exposure time and kilo-voltage, a properly exposed radiograph is obtained with a 6 milliamperes-minutes exposure at the distance of 20 in. It is desired to increase the sharpness of detail in the image by increasing the source-to-film distance to 40 in. The correct milliamperage-minutes exposure to obtain the desired radiographic density at the increased distance is:

Back 47

24 milliamperes-minutes (doubling the distance increases the exposure requirement four fold according to the inverse square law)

Front 48

The exposure of personnel to x-ray and gamma radiation can be measured or monitored by means of:

Back 48

film badges, dosimeters and radiation exposure survey meters

Front 49

Assuming that a good radiograph is obtained at a setting of 10 milliamperes in 40 sec., how much time will be necessary to obtain one equivalent radiograph if the milliamperage is changed to 5 milliamperes (all other conditions remain contant)?

Back 49

80 seconds (The inverse square does not apply here and cutting the amount of x-rays produced would double the exposure time)

Front 50

Short wavelength electromagnetic radiation produced during the disintegration of nuclei of radioactive substances is called:

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gamma radiation

Front 51

A photographic image recorded by the passage of x or gamma rays through a specimen onto a film is called a:

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radiograph

Front 52

The normal development time for manually processing x-ray film is:

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5 - 8 minutes in processing solutions at 68 degrees F

Front 53

In order to achieve uniformity of development over the area of x-ray film during manual processing:

Back 53

the film should be agitated while in the developer

Front 54

When referring to a "2T" or "4T" hole in the ASTM penetrameter, the T refers to:

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the penetrameter thickness (2T equals 2% and 4T equals 4% of the material's thickness

Front 55

A sheet of lead with an opening cut in the shape of the part to be radiographed may be used to decrease the effect of scattered radiation which undercuts the specimens. Such a device is called:

Back 55

a mask (because it "masks" out everything but the object being radiographed

Front 56

Two x-ray machines operating at the same nominal kilo-voltage and milliamperage settings:

Back 56

may give not only different intensities but also different qualities of radiation

Front 57

Fluoroscopy differs from radiography in that:

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the x-ray image is observed visually on a fluorescent screen rather than recorded on a file

Front 58

An advantage of the pocket dosimeter type of ionization chamber used to monitor radiation received by personnel is

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it provides an immediate indication of dosage

Front 59

The density difference between two selected portions of a radiograph is known as:

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radiographic contrast (the selected portions should be from the lightest and darkest areas of the radiograph to measure the overall image contrast)

Front 60

In making an isotope exposure in a unshielded area, you find the dose rate 6 feet from the source is 1200 mR/hr. What would be the dose rate at 24 feet?

Back 60

75 mR/hr (According to the inverse square law, increasing the distance by 4 results in 1/16th the exposure)

Front 61

The intensity of x-ray or gamma radiation is measured in:

Back 61

Roentgens per unit of time (Roentgens only refer to the ionization power of the radiation for one cubic-centimeter of air)

Front 62

The accidental movement of the specimen or film during exposure or the use of a focus-film distance that is too small will:

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result in unsharpness of the radiograph

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