224 

 for desorption of trapped volatiles onto the cryo-focusing trap. The cryo-focusing 



trap was set a -160°C for concentration and heated ballistically (over 10 s) to 150°C 



to purge volatiles onto the head of the GC column. 



The GC employed was an HP5890 series I with a 30 m x 0.25 mm i.d. DB-1 

 column (df= 1 jim) for initial experiments. Experiments with the hand enclosed in 

 a Tedlar bag were conducted on a 60 m x 0.25 mm i.d. DB-1 column (df=l ^m). 

 The column was initially cryo-cooled at -35°C and held for 3.0 min. Subsequently, 

 the column was either ramped at 127niin up to 180°C, then ramped at 257min from 

 180°C to 225°C and held for 5.0 min at 225''C, or in later experiments, the column 

 was held 6.0 min at -35°C then ramped at 67min to 180°C and 127min from 180°C 

 to 225°C, and held for 10.0 min. 



The mass spectrometer used for these studies was a Finnigan MAT Incos 50 

 single-stage quadrupole. The scan rate employed was 0.75 s per scan. The filament 

 emission current was set at 750 ^A with an electron energy of 100 eV. The electron 

 multiplier was set to -1200 V. The ion source temperature was set at 180°C; there 

 is no heater for the manifold. Prior to analysis, the instrument was tuned with 

 PFTBA and the appropriate blanks were analyzed. 



Case Study Comparison of Emanations between Subjects 



A series of experiments were conducted comparing emanations desorbed off 

 of beads handled by Mr. Carl Schreck and Mr. Dan Smith. Mr Schreck, in 

 entomological assays via an olfactometer, consistently provides relatively low 



