Lesson 2/Learning Event 8
covered between any two consecutive readings will be the same. Thus, if the route is divided
into a number of equal-length segments where the total number of segments is equal to the
number of time intervals, each division point on the route will represent a location over which a
dose-rate reading was taken. The interval between readings is equal to the length of the course
leg or route divided by the number of readings less one.
Post the normalized dose rates on the worksheet overlay beside the location point for the route as
the dose-rate readings are processed.
For example, figure 20 on page 73 shows the points along route (1) to (2) over which readings were
taken. In this case, seven readings were taken, but the route is divided into only six (6 = 7 - 1) segments.
Therefore, divide the route into a number of equal-length segments equal to one less than the number of
readings taken by the survey party.
Aerial Survey Course Leg Technique. Dose-rate information from an aerial survey conducted by the
course leg technique is plotted using the same procedure as that established for route techniques. The
only difference between the two techniques is that in the route technique the survey party will proceed
between two check points over a feature such as a road or railroad, whereas in the course leg technique
the survey party will proceed on a straight line course between the two check points. The two check
points are marked and labeled on the worksheet overlay and a straight line is drawn between them. The
aerial survey overlay shown in figure 21 on page 75 depicts course legs that were to be flown over an
area predicted to receive fallout. To illustrate the plotting procedures, assume that the course leg
between preselected check points 5 and 20 is 5.25 km long. The aircraft flew at a constant speed of 90
kmph, taking readings every 15 seconds for a total of 15 readings. Reading #1 would be plotted at
check point 5. The distance between readings is computed as
divided into 14 segments of 375 meters. Reading # 15 then falls on check point 20.