high-range film followed by the low range.:
The racks were placed in the developing solution and agitated for 4.25 min. They were
removed and allowed to drain for 15 secs, They were then placed in the stop solution for 20 sec
and then fixed for 10 min. As a final operation the film was washed for 30 min to remove all
traces of the three developing solutions.
Following the washing the film was dried for 30 min at a temperature of 100°F while still
in the racks.
B.5.3
Density Determination
The densitometer and the attached voltage regulator were allowed to warm up for 30 min
to eliminate drift.
The densitometer was then zeroed, and the calibration wedge was usedto fix one point on
the scale. The film-badge readings were taken from the area that was under the lead strip,
and the density was recorded on the laboratory processing sheet. The density was converted
to dose from a table prepared from the calibration curve.
To allow for changes in background, the densities of the controls were converted to dose,
and the average was subtracted from the dose of the personnel film badges. This adjusted dose
is recorded on the laboratory processing sheet. (The density of the controls cannot be subtracted from the density of the exposed film badges because the slope of the calibration curves
is not constant.)
B.5.4
Standard Film Error Adjustment
If the standard film dose, after adjustment for control variations, was still in error by an
amount greater than 10 per cent, all film-badge doses were multiplied by the ratio of the correct standard dose to the dose obtained.
B.5.5
Filing and Records Transfer
Each night, as soon as the processing was completed, the issue sheets were separated, and
the duplicate was immediately sent to the otheratoll.
The laboratory processing sheets were made in duplicate, and the duplicate was immediately forwarded to the otheratoll.
B.5.6
Film-badge Storage
After being processed, the personnel film badges were placed in small envelopes and
stored in oblong white boxes in numerical order.
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