dhi ee
D.
*
E,
re me oe
<
=
Sr90 Air Concentration, Port Lyautey, Morocco
61
Sample Number
Collection Period
Sr90/106ft3
CL 206B
July 9-11, 1953
9.70 x 0.45
CL 206C
July 11-13, 1953
38.6 + 1,2
CL 206D.
July 13-16, 1953
CL 206A
Sept. 30-Oct. 1, 1953
20.1 + 0.6
CL 2068
Nov, 2-9, 1953
8.10 + 0.22
CL 05-P
Nove. 8-9, 195)
155 + 1h
CL h06-P
Dece 3-4, 195)
214 + 20
CL 416-P
Jan. 4-6, 1955
58.1 + 10.0
CL 530-P
Feb. 28-Mar. 2, 1955
552 + 110
CL 531-P
March 6-8, 1955
430 + 60
CL 532-P
March 16-18, 1955
313 + ho
CL 533-P
March 22-21, 1955
119 + 25
;
8.70 * 0.33
Multivie Filters
Multiple filter collections were made by the Naval: Research. Labora~
tory, Washington, D.C., using a set of three filters in series, with
flow rat maintained at 20°CFM, The two week coliection volume is
4.0 x 10 cubic feet, The top filter, changed daily, is a viscose
filter which gives 75% penetration of 1.0 » particles and 85% penetration of 0.3 p particles at this flow rate. The middle filter,
also viscose, gives 25 and 50 percent penetration of 1.0n and
0.3 p particles, respectively.
The bottom filter is Army Chemical
Corps Type 7 (asbestos filter) of very nearly 100% retention.
Table IV
MULTIPLE FILTER DATA
Sample
Number
-
Filter .
CL 539-P Top - Mult, #1&2
CL 50-P Middle
Collection
Period
1/31/55-2/1h/55
Comb, No. D.P.M. Sr9O % of sr90
of Papers
Total Frac.
Activity
1b/l ad
23.0 + 1.5
4h.0
*
"
a,
n
2/lwk
13.9 + 1.2
26.6
CL 51-P Bottom "
"
"
"
2/ltk
15.4 + 1.0
290k
U/ld
37.2 + 2.1
5149. ARCHIVES
CL 542-P Top — Mult. #3&,
2/14/55-2/28/55
CL 5)3-P Middle "
. ©
"
"
‘2/lwk
=612.8 + 0.8
17.8
CL Suu-P Bottom "
1
fn
n
_O/lwk
21674 2h
3043
137