Mir Space Station Trace Contaminant Assessment 961472
Eight SUMMA passivated sampling canisters were shipped to the Russian Space Station Mir in February of 1995 to assess ambient trace contaminant concentrations. Prior to flight, the canisters were injected with isotope labeled surrogates and internal standards to measure potential negative impacts on measurement accuracy caused by the trip environmental conditions of launch and return. Three duplicate canister samples were collected in parallel with Russian sorbent samples to acquire data for comparative purposes.
A total of 32 target and 13 non-target volatile compounds were detected in each of the samples analyzed. The concentrations of the compounds remained relatively consistent for the three sampling events, and all of the concentrations of detected contaminants were well below both US and Russian Spacecraft Maximum Allowable Concentrations (SMAC). Five different fluorocarbons were consistently detected at relatively high concentrations. Octafluoropropane is the approved refrigerant for use on Mir, and it was found at significantly higher concentrations than other fluorocarbons. Other major identified trace contaminants included alcohols, toluene, xylenes, acetone, xenon, and a variety of terpinoid compounds.
Comparability of data acquired from the canister and the Russian sorbent tubes was very good for a number of applicable compounds. Analytical findings indicate that the canister and sorbent sampling procedures are complementary over a broad spectrum of polar and non-polar contaminants. The deuterium-labeled surrogates were recovered with high accuracy and precision, and no negative impact of environmental factors was measurable. All project quality goals were achieved. Of 321 quality verification measurements, 314 achieved pre-defined project acceptance and guidance criteria, providing an overall quality completeness factor of 98 percent for the modified EPA Method TO-14 canister method.