Handbook of Solvents - George Wypych - ChemTech - Ventech!

1224 Margot Scheithauer
an initial 48 hours without an air
exchange in the test chamber, in
order to simulate a “worst case
scenario”, i.e., that, for instance,
the new furniture is sealed off
air-tight during transport, so that
residual solvents accumulate.
After 48 h of storage time
without an air exchange, air samples
are taken in parallel for the
determination of VOC emission
by means of gas chromatograph
and for determination of odor by
the olfactometer. Subsequently,
there is an air exchange of one air
change per hour, and the
slow-down curve of VOC and
odorant concentration is determined.
Figure 18.1.11 shows the decreasing VOC concentration depending on the storage
time in the test chamber with an air exchange 1, 50,46 and Figure 18.1.12 shows the decreasing
odorant under the same test conditions. 50,46
The curves for VOC and the odorant concentration follow a similar pattern, they are,
however, not identical. While the VOC concentration in water varnish is the lowest after 11
days, the odorant concentration after this time is equally high with both DD-varnish and water
varnish. This, however, does not generally apply to these types of varnish. Also DD-varnishes
of different origins may differ greatly in emitting residual solvents.
In single-solvent systems, it is easy to see the interdependence between VOC and
odorant concentration. This does not necessarily apply to solvent mixtures. This is due to
the large variations in odor thresholds and the different evaporating behavior of the various
solvents.
Acrylate varnishes, for example, need contain only a few µg of ethyl acrylate in order
to produce odor, since odor threshold level is at 0.002 mg/m 3 Figure 18.1.10. Test approach for the determination of VOC and
odorant concentration in coated surfaces.
. Thus the determination of the
Figure 18.1.11. VOC concentration depending on the
storage time in the test chamber with air exchange 1.
Figure 18.1.12. Decreasing odorant concentration depending
on the storage time in the test chamber with
air exchange 1.