Space Grant Consortium - University of Wisconsin - Green Bay

there was no dichlorobenzene peak. GC spectra confirmed that no dichlorobenzene could be
found in the sample. Considering dichlorobenzene was present in both samples, a large peak
was expected but not detected.
One of the challenges of this data was comparing effects of the sample and mix on peaks areas
when the amount of Mix 4 used was different between chambers. Peak areas varied a lot simply
due to the volume difference of Mix 4, making it difficult to analyze. Unfortunately by the time
this was realized the solution of Mix 4 had been used up and there was no way to further analyze
the interactions of the Mix and sample.
Peak areas for offgassing of 108148 were expected to decrease with decreasing temperature.
This happened for the first two runs, and after that there was a general decreasing trend.
However, different peaks increased and decreased at different points, suggesting the relationship
was not that simple between peak area and temperature.
Data from 107999 showed more identifiable offgassing which was helped by using 15.0g of
sample as opposed to 5.0g. For the most part these results showed a more consistent decrease in
peak area over time. For both 107999 and 108148 the peaks at 97 and 96 minutes had
inconsistent areas for each column. The 107999 front peaks had small areas while the back
column peaks had large areas. The opposite was true for 108148 which had large front column
peak areas and small back column peak areas. While there is no clear explanation for why these
peaks at about 96 minutes were inconsistent, the fact that it was observed in both samples
suggested it was significant.
Conclusion
These experiments involved studying a variety of aspects of toxicity testing. Standard Mixes
were used to look at response factors and detection limits of a variety of molecules. Mixes were
also used to look at their interactions with materials, with limited success. Peak area dependence
on temperature was investigated using material samples. Knowledge learned from these
experiments served as part of continuous efforts to improve toxicity testing and the
understanding of it.
References
EM10-OWI-CHM-039, Revision B (Marshall Space Flight Center) “Determination of Offgassed
Products Testing (Toxicity),” November 28, 2007.
NASA-STD-6001 “Flammability, Odor, Offgassing, and Compatibility Requirements and Test
Procedures for Materials in Environments that Support Combustion,” February 9, 1998.
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