as
In addition to general information on the nature of radioactivity, and on the means for its detection and measurement, this
manual eontains operating instructions to aid laboratory personnel in
carrying out their duties. Considerable information giving a general
packground in the field of radiological effects has been included to
assist personnel in the performance of duties for which no adequate
CS,
instructions can be prepared.
t)
de
-
CRLR - 117
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THE CONTAMINATION OF A VEHICLE ENGINE (WC 54) WITH
RADIOACTIVE SAND, AND ITS DECONTAMINATION.
M. G. Gordon, H. A. Chambers, and L. A. Ford, 9 February 1953.
CONFIDENTIAL
bh
we
To determine the location and extent of radiological contamination of a running vehicle engine, fine sand tagged with aged (1-4 yr)
fission-product solution was introduced into the engine intake-air through
an air filter, Fifty grams of such contaminated dust was introduced into
a special chamber surrounding the air filter, over an 8-hr period, at a
rate corresponding to 0.025 g/cu ft of combustion air.
This arrangement
was effected by operating the engine at 1,300 rpm, equivalent to a speed of
hr.
30 mi/hr.
0
mxternal monitoring gave no indication of the hazard involved
in servicing contaminated vehicle engines.
The metal and air shielding
afforded by the engine and its location in the vehicle was such that
contamination within the engine could not be traced externally. Radio-
activity varied from (relatively) very high in the air filter, carburetor,
and engine head to low in the exhaust system, valves, and pistons.
7.
reduced criginal contamination readings ranging between 4,000 and 43,000
LE
counts/min to residual readings of from 1,300 to 1,500 counts/min.
CRLR ~ 120
-
;
PRELIMINARY CALCULATIONS ON THE EFFECTIVENESS OF SMOKE AT
OPERATION KNOTHOLE.
Charles S. Brice, Jr., 24 March 1953.
SECRET-RESTRICTED DATA
On the basis of experimental data obtained by using a collimated
ion
oratory
fects
Con-
taminaticn in the crankcase and the oil filter was found to depend on
engine ccndition, with little contamination in these locations if piston
rings were close-fitting.
Decontamination was easily effected in most
cases by simple techniques, such as wiping or brushing.
These techniques
~
beam oF light, prediction is made of the degree of attenuation of thermal
radiation by a white, oil-fog smoke, and of the temperature rise within a
carbon smoke.
7O mmg/l.
REST
ATOMI
Calculations were based on smoke concentrations up to
- 1954
oe