COREE

|

It includes a description of the physical setup necessary for such
a study, & comparison of results with the theoretical results of
standard sources and a discussion of the problem of self-absorption
and self-scattering in the sample.
It is concluded that sources composed of mixed nuclides can
be accurately measured by an absolute beta-counting system and that for
samples having considerable mass-per-unit area self-absorption and
self-scattering become important factors, especially for low-energy
radiation.
These effects can introduce large errors unless they are
properly sc
attered. B
EST AVA
ILABLE
Copy

CRLR - 571

-

<A LABORATORY INVESTIGATION OF THE EFFECTS OF CLIMATIC

ENVIRONMENT ON AW AND RW DECONTAMINATION (C).

Malcolm G. Gordon and Robert J. Smith, 9 April 1956.
SECRET-FORMERLY RESTRICTED DATA, Interim Report

(U)

The effects of environmental temperature, humidity, rainfall,

wind speed variations, and type of soil upon the ability to clean surfaces
contaminated bi RW and AW agents are presented.

Se

The conclusions of this report are as follows:
1.

A temperature of O°F and snow or ice can decrease decontamina-

tion efficiency; by one half and thus increase the quantity of water waste
by a factor of 2,
@.
Softening of materials by heat, causing particulate matter
to adhere, will decrease decontamination efficiency as much as 30%.

3.

Strong winds will move 30% to 40% of RW materials on smooth

4,

Rainfall will help in the decontamination of particulate

5.

The disintegration rate of lead oxide pellets is dependent

6.
water spray.

Of the soils tested, only clay was resistant to removal by

surfaces, but may result in pockets of high radiation levels.

matter, but may cause undesirable redeposition elsewhere.
Decontamination
efficiency may be reduced by 20% if performed after drying of moisture.

on humidity ani temperature, while the ultimate particle size distribution is not arvreciably affected.

Select target paragraph3