7
‘
collected water vapor with water on this large surface either adsorbed,
or as liquid not removed in the original packaging, and with a relatively
high permeability of the polyethylene bag to water vapor, it cannot be
maintained that any T/H value measured in the final samples is representative of the air at the collection altitude.
It appears that such
ratios will best be determined by an independent measure of the water
vapor content of the air at high altitudes coupled with the tritium
content as measured here.
h,
k,l
ERRORS
Tracer
The amount of tracer added to the collection of air is estimated
to be accurate to about 1 per cent.
h.2@
Deuterium and Tritium
Deuterium concentrations are measurable to + 4 per cent.
Errors
in the measurement of tritium amount to about 10 per cent, 5 per cent
attributable to statistical counting errors and 5 per cent to calibration
errors.
Careful control
in the source of the tracer deuterium oxide results
in a tracer containing less than 250 Gpm of tritium per gram.
This is
normally only about 5 per cent of the total tritium in a sarple end
therefore uncertainty arising from tritium in the tracer is negligibly
small,
The method of determining the volume of air collected is estimated
to have a stancard error of about + 5 per cent.
However,
the density