2h-hour samples per day.
Similarly, isolated collections of
activity appear in areas distant from those affected by airborne
debris. Such errors indicate the caution which should be
exercised in examining individual values. The emphasis, rather,
should be on the broader aspects where the presence of corroborating
- information lends credence to the individual samples.
DEPOSITION
L.
va
1.5.1. Bry Fallout
,
|
It dg Mikely that the gumed paper collects more
activity than remains on the ground in periods of dry weather when
the wind cam pick up debris which has already fallen out. This is
especially true in dusty locations.
The effect of rain running or
¢ splattering off ‘the
gummed paper and carrying with it some debris and soluble ratioactive material, must be important, but no information is available
on this subject. It is believed that more debris will be lost in
the heavy tropical showers thm in lighter steady rains of the
temperate latitudes.
ink
wr
1.5.2 ‘Retnout
1.5.3
Effect ofthe Particulate Nature of Debris
If activity is concentrated on a relatively amal?
mumber of large particles, it is possible that the small area -
sampled by the gummed paper may not be a statistically signifi-
cant sample. The duplicate papers, exposed within six feet of one —
another ee
showed large differences, which ere discussed
in Section 6.2.
;
1. 3.i
Other Factors
The effact of elevation of gummed papers some three
feat above the ground is unimow, as are the effects of tempera- .
ture, dust, humidity and water on the adhesive properties of the
gummed papers. These factors may be significant but cannot be
evaluated here.