Thermo Scientific SAM12, Руководство пользователя

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Issue: 1.0 Technical Description - Physics
Thermo Fisher Scientific SAM12 User Manual 6-9
Quickscan is a method used to identify, within the monitoring
time T
mon
, whether the article is either “clearly” contaminated
or clear, referred to as “real-dirty” or “real-clean”. Quickscan
is enabled on the Options sub-menu (see
Options (page 5-6) ).
It is only activated when T
mon
>T
min
The Quickscan period T
Q
is the time period after the beginning
of the monitoring cycle, at which the first time slice check is
undertaken. Subsequently further Quickscan checks will be
undertaken at periods that are integer multiples of T
Q
e.g. 2T
Q
,
3T
Q
, until the end of the monitoring period. The Quickscan
period is set on the Params 2 sub-menu (see Params 2 (page 5-
10) ).
If the Quickscan formula (refer to Thermo Fisher) is satisfied at
any of the Quickscan checks, then the monitoring cycle will
terminate, with the appropriate clean or contaminated
indication.
After a measurement resulting in an alarm, an NBR check may
be undertaken, if enabled on the Options sub-menu (see
Options (page 5-6) ).
For details of the NBR assessment, please contact Thermo
Fisher Scientific.
A specific assessment of
60
Co contamination may be
undertaken, if enabled on the Options sub-menu (see Options
(page 5-6) ). Further an alarm may be triggered specifically for
60
Co, although in most situations this alarm is unlikely to
trigger before the Normal alarm.
The method of assessment of background count rates and
contamination level, applies to the CCM channel in the same
way as for the sum of all detectors (gross sum channel)
described in this section. However both the background count
rate B
CCMsum
and the efficiency E
CCM
, are considerably lower
than for the gross sum channel.
For details of the CCM assessment, please contact Thermo
Fisher Scientific.
After a measurement resulting in an Alarm condition, a
Residual Contamination Count (RCC) may be taken, if enabled
on the Options sub-menu (see
Options (page 5-6) ). A count
equal to the monitoring time (T
mon
) is enforced.
Quickscan
Natural Background
Reduction (NBR)
Cobalt Coincidence
Monitoring (CCM)
Residual Contamination
Level