TABLE 3.1
ALTITUDE RADIATION DATA OVER LAND (ENIWETOK ATOLL)
Altitude
mr/hr*
mr/hrt
mr/hrt
mr/hré
mr/hrd
mr/hr**
ft
1,000
1.0, 1.1tf
800
130
1.5
600
180
1.8
500
0.7
18
400
5.7
2.8
300
1.0
1.2
200
1.9
1.9
100
75
500
950
4.1
30
8.5
42
12.5
70, SStt
:18.0
1,200
50
2.5
2.3
1,700
11.0
* Mohawk + 2, over Tilda, scintameter TH-3, S/N 25 in helicopter.
+ Mohawk + 2, over Tilda, scintameter, TH-3, S/N 2 in helicopter.
t Mohawk + 2, over Sally, scintameter, TH-7, S/N 3 in helicopter.
§ Seminole D-day, over Janet, scintameter TH~-3 in helicopter.
1 Mohawk + 1, over Janet, scintameter, TH-3, in P2V-5.
** Mohawk + 1, over Janet, Top Hat radiation detector in P2V-5.
tt Values from repeat runs.
gamma-emission energy that is considerably softer than the radium used in instrument calibration, the sodium iodide detector should read high on an actual survey.
The data in Table 3.1 were normalized to the theoretical curve, and are shown in Figures 3.2
and 3.3.
& Seminole 0-Day~Scintometer - Over -Janet
40 Mohawk D+2-Scintameter-Over-Sally
O Mohawk D+2-Average of 2 Scintameter-Over - Tilda
Percent of 3- Foot Dose Rate
—
°
200
400
600
800
1000
1200
Altitude , Feet
Figure 3.2 Radiation attenuation over land (Helicopter).
Table 3.2 summarized the data obtained over water, and these are plotted in Figure3.4.
Additional data of this type have been derived from measurements made in previous operations.
This information is presented in Appendix C. The curves in Figures C.1 and C.2 show a similar
correspondence to the theoretical curves.
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