health and safety laboratory - Digital Collections

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stations having only gummed film sampling by the use of a regional Pot/Gummed
Film factor. As an example, the following table was developed from the north
ern hemisphere stations where pot data were collected.
Average Pot/Gummed Film Ratios for the Northern Hemisohere
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Month 1957 1938
Jan, 1.4 1.6
Feb. 1.3 1.8
Mar, 1.2 1.1
Apr. 1.4 1.0
May .9 1.6
June 1.0 2.4
July 1.1 1.2
Aug. .7 2.1
Sept. .5 2.3
Oct. .7 2.0
Nov. 1.3 2.0
Dec. 1.1 2.5
Mean Ratio 1.0 1.8
These average ratio factors can still yield
Ig59
2.1
2.0
2.8
2.1
1.6
2.5
2.6
1.9
1.5
2.1
2.4
3.5
2.3
only an approximation and
while the second is approximately T+0 * 7^ for the first year and T * therei
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probably hold only for the northern hemisphere.
There is some justification for applying the
finity gamma dose data as well. Most of the errors
same factors to the incan
be divided into two
classes , poor collection of fission products and those involved in the model
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computation. Poor collection would affect the Sr and 7 dose values equally.
The computation model is equivalent except for the
QO
factors of % Sr , and of
7 disintegrations per p dpm. The first is approximately at T * function,
after. Thus, the average Pot/Film ratio may be a reasonable correction factor
There has been no attempt in this report to
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distribution of Sr 7 . The data do not warrant this , as soil and pot analyses
are more reliable for this purpose.
depict the geographical
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