Continuous monitoring requires that the monitor have the survey meter turned
on at all times; the frequency of readings will depend upon the current
situation. For example, the monitor will take more frequent readings when
fallout is actually arriving on the unit position than when the unit is
simply warned that it may be in the fallout area.
Units initiate continuous monitoring in the following situations:
■
When a fallout warning (NBC 3 Report) is received.
■
When ordered by the unit commander.
■
After a nuclear burst has been sighted, heard, or reported.
■
When the unit is moving.
■
■
When radiation above 1 cGyph is detected by periodic monitoring.
Units discontinue continuous monitoring on orders from higher headquarters
or when the dose rate falls below 1 cGyph except for units on the move.
2.
Monitoring Techniques.
Monitoring techniques vary, depending upon such factors as ground dose rate,
operational or tactical conditions, dose status of monitor, type of survey
meter, and whether the monitor is stationary or moving. The technique used
must provide sufficient information to allow evaluating agencies to
calculate the ground dose rate at the monitor's location. DA Form 1971-R is
used for recording monitoring data and for survey data when point or
preselected dose rate techniques are used.
a. Direct Technique.
The direct determination of ground dose rate is the simplest and most
precise of the monitoring techniques. The unshielded ground (outside) dose
rate may be determined directly by standing at the desired location, holding
the survey meter waist high in a vertical position (face up), turning with
the survey meter in all directions, and recording the highest dose rate
reading observed. The preferred procedure is to take readings in the open
at least 10 meters away from buildings, other large structures, or objects
that may shield out a portion of the radiation.
If there are points of
operational interest where this procedure cannot be used, additional
readings can be taken at those points. Thus, if a road through a narrow cut
or defile is of operational interest, readings should be taken both in
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