APPENDIX
UNCLASSIFIED
5
ESTIMATE OF COLLECTION EFFICIENCY OF FILTERS USED IN JET A
rilter papers were placed in series during two flights. If we as
titers do not significantly discriminate according to particle siz
afficiency can be estimated as follows.
Let 8 2 fraction of activity retained on filter
CG = Activity in volume of air sampled
A, and A, = Activity collected by first and second
filters respectively
Then
4, = EC
Ay = (1-k) 0
Rzle- é
The following data were obtained:
November 30, 1953
First filter in series
Secon filter in series
S
780 d/sin
60 d/sin
Bra Si
x
2 .92
as
December 15, 1953
a
Firet filter in series
#.
Second filter in series
ns
2070 d/min
140 d/min
R=1- 10
2070
HT
|
|
= 9
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