FIFTH CANADIAN CONFERENCE ON NONDESTRUCTIVE ... - IAEA

INTRODOCTIOM (Continued)
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Quality control means consistent, measurable quality. An automatic processor
provides this to a degree superior to controlled manual processing.
It is important to understand the prejudices and history before trying a new
method, if the new method is to succeed.
SELECTING A PROCESSOR
Many people gravitate toward the smallest, cheapest unit available. Unfortunately
this means a medical unit slowed down. The result is low capacity
and perhaps increased mechanical load. The ideal processor for NOT applications
is one with 5 to 10 gallon tanks, preferably plastic for greatest
temperature stability, bellows replenishment pimps which are the most accurate
and a transport rate sufficient to produce 50 films per hour on an eight
minute cycle. Of course price must be considered, but it should be considered
in relationship to film capacity and darkroom personnel costs. This
translates into a cost per film. If the processor has built-in variable
drive, cold water washing, water saver, and automatic standby then other
savings are applied to reduce the cost per film.
INSTALLING A PROCESSOR
Processors may be located through darkroom walls, or be placed totally in
the dark. Or it may be totally in the light as when a Du Pont Daylight
Module is used. Some processors can also be placed in trucks, trailers,
airplanes, and on barges and ships. The only criteria is to provide service
room to all sides and to consider the ambient conditions. In the first
case, about two feet is needed on all sides of a processor. In the second
case, ambient conditions include the room air, moisture, and quantity of
metal filings and/or general dust present. The processor has a powerful
blower that draws in 100-200 cubic feet per minute of air to dry the film.
The air should be relatively clean, cool, and dry. Metal filings affect all
developers, but would tend to drawn toward an automatic processor more than
a manual one. Physical installation is described in the installation manual
of the processor.
ADVANTAGES/DISADVANTAGES
The automatic processor offers high volume, consistent quality in a small
package. An untrained darkroom person can produce good films immediately,
or in eight minutes. If the processor is monitored periodically, which is
referred to as sensitometric quality control testing, to insure that it is
indeed consistent, then it is a simple device important to production.