02 Processing Room Design

40%-60%.

Relative humidity

<20 degrees C/68 degrees F (Bushong).

Room temperature

8-10 per hour (exhaust fan).

Air changes

To prevent buildup of fumes from chemicals used in the processor system; air from the dryer system must be vented outside the darkroom.

Purpose of air ventilation

Device used to measure humidity/moisture.

Psychrometer

Films should be standing on the edge to avoid pressure marks and should be stored in film storage carts or shelves.

Proper film storage

The simplest type; needs to provide a passbox.

Single Door

Avoid RT in entering the darkroom.

Rationale of Single Door

Inexpensive; not space-consuming.

Advantages of Single Door

Not truly lightproof; poses a safety hazard.

Disadvantages of Single Door

Used only when there is darkroom personnel exclusive in the darkroom.

Double Door

If door 1 is open, door 2 is closed (Electrical interlock).

Double Door Mechanism

Zigzag type; used only when the darkroom is large.

Maze/Labyrinth Type

Requires more space.

Rationale of Maze Type

Easy access.

Advantage of Maze Type

Fast access type; can enter and exit at the same time.

Revolving Door Type

Used for manual processing of films.

Processing Tanks

Machines for processing X-ray films.

Automatic Processor

Indicates that the darkroom is in use.

Warning Light outside the door

Prevents unauthorized access.

Lockable Door

Storage for unexposed films.

Film Bin

Area for handling films before processing.

Loading Bench

Allows film transfer without opening the darkroom door.

Passbox

Provides general illumination.

Fluorescent Light

Provides safe working light without fogging films.

Safelight

Used for cleaning and maintenance.

Wash Basin

For drying processed films.

Drying Cabinet

Used in manual film processing.

Hangers for suspending films

Provides sufficient darkroom illumination without affecting film.

Safelight

X-ray films are color sensitive, restricted to a specific range of wavelengths; safelight allows non-sensitive wavelengths while cutting off white light.

Principle of Safelight Operation

Amber filter; safe for blue-sensitive films.

Kodak Wratten 6B Filter

Dark red; low intensity, more versatile, and can be used for green and/or blue-sensitive X-ray films (Orthochromatic film).

Kodak GBX-2

Ensures safe handling of unprocessed films.

Film loading/unloading areas

Prevents film fogging during transfer.

Processor film feed-in points

Allows monitoring of film processing.

At developer tank

Should be properly adjusted.

Safelight to film distance

Should be kept low.

Bulb wattage

Minimized to avoid excessive exposure.

Number and location of bulbs

20-45 secs to avoid post-exposure fog.

Film handling time

7.5 W.

3 feet

15 W.

4 feet

25 W.

1.2 M

Fogging of the film by safelight illumination after radiographic exposure; appears as an undesirable density on the processed image.

Post-Exposure Fog

Used for inspection, maintenance, cleaning, and servicing of equipment.

Purpose of White Light

Should be close to the ceiling.

Placement of White Light

Moderate (60W tungsten or 30W fluorescent).

Intensity of White Light

Centrally placed for uniform illumination.

Location of White Light

Maintain cleanliness daily.

Darkroom Cleanliness

Replace filters and service air conditioning.

Air conditioning

Wipe with a damp cloth.

Countertops

Wipe with anti-static solution.

Film trays

Use white light during cleaning.

Cleaning

Prohibited in the darkroom.

Smoking

Not allowed in the darkroom.

Eating

Should not be done in the darkroom.

Drinking