Quality Assurance and Quality Control Tests (PART I)

darkroom

lightproof space designed for developing x-ray films into visible diagnostic images using chemical solutions or an automatic processor

2-8

film that has been exposed to light or ionizing radiation can be as much as ___ times as more sensitive to subsequent exposure compared to an unexposed film

latensification

increase in sensitivity after exposure is known as

- excess heat

- humidity

- static electricity

- pressure

- chemical fumes

film can also be affected by (5):

- clean

- well-ventilated

- well organized

- non-smoking zone

- static free

OSHA classifies a darkroom as a laboratory, at minimum it should be (5):

ventilation

prevents build-up of heat and humidity; removes excess fumes from processing solutions that may sensitize film emulsions

near the floor

a ventilator duct should be placed ____, in either the lower portion of the entrance door or the wall

30% to 60%

proper humidity range is __ to __ of relative humidity

psychrometer

humidity is monitored using a

humidity

minimizes induction of static electricity

65° - 75°F (18° to 24°C)

temperature range should be

- toxic

- corrosive

- potentially carcinogenic

fumes from the processing solution are considered (3):

25 mg/m3 (10 parts per million , ppm)

acetic acid:

35 mg/m3 (50 ppm)

ammonium thiosulfate (as ammonia):

2 mg/m3 (0.44 ppm)

hydroquinone:

19mg/m3 (5 ppm)

phenol:

13 mg/m3 (5 ppm)

sulfur dioxide:

0.7 mg/m3 (0.2 ppm)

glutaraldehyde:

0.01 mg/m3

silver:

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 (3):

- humidity and temperature is within range

- chemical exposure are well below PEL

indications of proper ventilation (2):

adequate drainage

darkroom must have

2.5x

darkroom must have the capacity to handle ___ the maximum outflow of the processor when all drains are open

enamel or epoxy

darkroom walls should be in ___ or ___ paints in pastel and light colors with matte finish

adjacent

darkroom should be ____ to a radiation area, and the walls should have equivalent shielding

upright

films must be stored in ___ position

film transfer system (passbox)

should be present to prohibit white light from entering

- countertops or other work surfaces and rubber floor mats should be grounded

- proper film handling

- wear natural-fiber clothing (cotton) versus synthetic fiber (nylon, polyester)

- maintain proper humidity range

- humidity can be measured using a psychrometer

- clean screens regularly with an antistatic non-abrasive cleaner

static reduction is minimized by (6):

- overhead lights

- safelights

two types of darkroom lighting:

standard white light

necessary for cleaning, maintenance, and possible emergencies (e.g., darkroom personnel becoming ill)

2-4, 48 in. fluorescent tubes per 8 square feet of floor space

overhead lighting should have a standard fluorescent fixture of

overhead lighting

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 are placed ___ feet away from feed trays or loading counters to minimize fogging

7.5 W or 15 W

average-sized darkroom, fixture type of safelight containing either a ___ or ___ light bulb

filter

bulb is covered by a colored piece of plastic or glass called a

- Kodak Wratten 6B

- Kodak Mor-Lite

most common type of filter used (2):

sodium vapor lamp

is used especially when bright safelight conditions are desired (large darkrooms)

6 feet

sodium vapor lamps must be mounted on the darkroom ceiling at least __ above the counters and film bins

blue-violet sensitive film

- most common type of film used in screen cassettes

- sensitive to blue, indigo, and violet

amber-colored

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

orthochromatic film

- mainly sensitive to the green portion of the spectrum in addition to the blue-violet portion

- uses the same safelight with the same fixture

red or magenta

___ or ___ dye is added to the film emulsion to increase the absorption of green light by the silver halide crystals

- Kodak GBX (green/blue/x-ray) series

- Kodak 2 filter

- LED safelight

orthochromatic film, most common type of filter used (3):

panchromatic film

- sensitive to all colors of the visible spectrum

- fixture and light bulb combination safelight with a dark green filter can be used

- best to consult the literature accompanying the box of film or the manufacturer's technical representative before dark green safelight is used

Kodak Number 7

dark green safelight usually used for panchromatic film