QAQC Tests

Darkroom

Lightproof space designed for developing x-ray films

into visible diagnostic images using chemical solutions

or an automatic processor.

2-8, latensification

Film that has been exposed to light or ionizing radiation can be as much as ... times more sensitive to subsequent exposure compared to an unexposed film. This increase in sensitivity is known as ...

30 - 60%

Proper darkroom humidity range is ... to ... of relative humidity

Psychrometer

Humidity is monitored using a ...

Static electricity

Humidity minimizes induction of ...

65° - 75°F (18° to 24°C)

Temperature of darkroom

Toxic, corrosive, and potentially carcinogenic

Fumes from the processing solution are considered:

Environmental engineer

... can be consulted to monitor the

chemical exposure levels in a darkroom area.

Darkroom disease

a condition by radiographers and

darkroom technicians in where they have hypersensitivity to

darkroom chemicals

- hives,

- severe fatigue,

- impairment of the immune system

Symptoms of darkroom disease

2.5x

Capacity to handle ... the maximum outflow of

the processor when all drains are open.

• Overhead lights

• Safelights

Two types of Darkroom Lighting:

Overhead lighting

- Necessary for cleaning,

maintenance and possible

emergencies

- should be interlocked with the film bin

Safelight

Light source that emits wavelength to

which particular types of film are not

sensitive.

3-4 feet

Safelights placed ... away from feed trays

or loading counters to minimize

fogging

Sodium Vapor Lamp

Safelight used for large darkrooms

￭ Kodak Wratten 6B

￭ Kodak Mor-Lite.

Average-sized darkroom,

Most common type of filter used:

7.5W or 15W

Average-sized darkroom - fixture type of

safelight containing either a ... or ... light

bulb.

⚬ Bul

Filter

Bulb is covered by a colored piece of plastic or glass called a ...

6ft

Sodium vapor lamps must be mounted on the darkroom

ceiling at least ... above the counters

and film bins

Blue-violet-sensitive film

Common type of film used in screen cassettes

Blue, indigo, and violet

Blue-violet-sensitive film is sensitive to ...

Amber-colored

...-colored safelight is normally used for blue-violet-sensitive film

Orthochromaric film

Film that is mainly sensitive to the green portion of the

spectrum in addition to the blue-violet portion

Green

Orthochromatic film is mainly sensitive to the ... portion of the spectrum in addition to the blue-violet portion

Red or magenta

Orthochromatic film: ... or ... dye is added to the film emulsion to increase the absorption of green

light by the silver halide crystals.

1. Kodak GBX (Green/Blue/X-ray) Series

2.Kodak 2 filter

3.LED safelight

Orthochromatic film,

Most common type of filter used:

Panchromatic film

Film that is sensitive to all colors of the visible spectrum

• Cracks or pinholes in the filter

• Wrong wattage of the bulb being installed

• Doors on a sodium vapor lamp being open too far

Safelight may become unsafe over time as a result of:

Semiannually

Safelight testing is done at least ... or more frequently if problems are discovered

1. Penetrometer

2. Sensitometer

Methods for safelight testing:

55-75°F (14-24°C)

Films should be stored at temperatures between ...

30-60%

Films should be stored at a humidity between ...

40-85°F (5-30°C), 70°F (21°C)

Chemicals should be stored at temperatures between ... and

should not exceed ... for an extended

period of time.

Thomas Alva Edison

Developed IS in 1896

1896

Thomas Alva Edison developed IS in ...

Michael Pupin

First used film/screen combination a year after

Luminescence

X-rays exiting the patient energize the phosphor crystals

which results to emission of light

Fluorescence

- light emitted within 10−8 s after crystals

are exposed

Phosphorescence

- light emitted sometime after 10−8s

after crystals are exposed

Intensifying screen speed

Refers to the amount of light emitted by the screen for

a given amount of x-ray exposure.

Intensification factor, relative name, or speed value

Intensifying screen speed can be measured by ...

Intensification factor

Exposure required to create a certain OD without a

screen divided by exposure required with a screen to

create the same OD.

IF = 𝑒𝑥𝑝𝑜𝑠𝑢𝑟𝑒 𝑤𝑖𝑡ℎ𝑜𝑢𝑡 𝑠𝑐𝑟𝑒𝑒𝑛/𝑒𝑥𝑝𝑜𝑠𝑢𝑟𝑒 𝑤𝑖𝑡ℎ 𝑠𝑐𝑟𝑒𝑒𝑛

Intensification factor formula

Relative speed

Most common method of designating screen speed

mAs

When the speed of the screen is changed, a change in ... is required.

New mAs = 𝑜𝑙𝑑 𝑚𝐴𝑠 ×𝑜𝑙𝑑 𝑟𝑒𝑙𝑎𝑡𝑖𝑣𝑒 𝑠𝑝𝑒𝑒𝑑 𝑣𝑎𝑙𝑢𝑒/𝑛𝑒𝑤 𝑟𝑒𝑙𝑎𝑡𝑖𝑣𝑒 𝑠𝑝𝑒𝑒𝑑

Formula for new mAs

Acceptance, year.y

QC testing of screen speed should be done on ... and then ...

- Multiple IS speed uniformity

- Single IS speed uniformity

A standard QC test would be to check for speed

uniformity and it is performed in two ways:

Multiple IS speed uniformity

Testing several IS of the same marked screen speed

Single IS speed uniformity

Testing a single IS