the open near the cut and in the cut. In cities or built-up areas, readings
are taken in the center of the streets or at street intersections. In all
these cases, no correlation factor data are required since the readings are
representative of the area of interest. Safety considerations may preclude
the direct determination of ground dose rates except--
When in low dose-rate areas.
While obtaining transmission factor data.
While moving through a contaminated area on foot.
b. Indirect Technique.
(1) Monitoring inside shelters.
Within the contaminated area, monitoring will normally be performed from
within shelters or fortifications.
The reading is obtained by noting the
highest dose rate measured by the survey meter when it is held in the center
of the shelter, 1 meter above the floor, and pointed in all directions. The
outside dose rate is then obtained by applying the correlation factor to the
inside dose rate reading.
(2) Monitoring inside vehicles.
Monitors mounted in ground or aerial vehicles use the ground or aerial
survey procedures to obtain monitoring information.
Correlation Factor Data.
All monitoring reports, except those made using the direct technique must
include correlation factor information so that shielded dose rates can be
converted to unshielded ground dose rates. If the situation permits, it is
preferable to determine the correlation factor directly. When correlation
factors cannot be obtained directly, the type of structure or vehicle should
be identified in the monitoring report and the appropriate correlation
factor should be obtained from Figure 4-1.