Lesson 2/Learning Event 4
Aerial Radiological Surveys
When a large area must be surveyed in a short period of time with little radiation exposure to survey
personnel, an aerial radiological survey should be conducted if weather and airspace control permit.
Aerial surveys can be conducted rapidly and at a distance from the radiation source. The aerial survey
party is exposed to considerably less nuclear radiation than a ground survey party over the same area.
For this reason, aerial surveys can be employed over areas that have dose rates unacceptably dangerous
to ground survey parties.
The advantages of an aerial radiological survey over a ground radiological survey can be summarized as
more speed and flexibility.
lower radiation doses to the survey party.
The disadvantages of aerial radiological surveys are that they
are dependent on weather and visibility conditions.
are less accurate than ground surveys.
There are two types of aerial surveys; the detailed aerial survey and the simplified aerial survey. Each
type of aerial survey is discussed in more detail below.
Detailed Aerial Survey
Monitoring reports and a simplified aerial survey do not normally provide sufficient information for the
required.
Planning. The basis for planning a detailed aerial survey is the check point overlay. Check points that
are easily identified from the air and on a map (small bodies of water, streams, or road junctions) are
selected for the entire area of responsibility of the major command. This is done in advance by the
chemical officer (or TOC representative) in co-ordination with the aviation officer. These check points
are maintained as an overlay by these two staff officers. Then, when a survey requirement is
established, the control party selects a series of course legs, routes, and points where data will provide
sufficient unshielded ground dose-rate information to evaluate the contaminated area. Figure 14 on
page 55 shows an overlay plan for an aerial
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