Expected Performance - Purge & Trap Concentrator
Thischromatogramwasproduced fromanalyzingawaterblank immediatelyafter theanalysisof the
BTEXPlusstandard toshow thePurge&Trapcarry-over. Theblankwas rununder thesameconditions
(event table, temperatureprogram,detectorsettings)as thesample. Acceptablecarry-over isacontamination
levelof1%or0.5ppb—whichever is lower—ofananalyte (especiallyhighboilingcomponents), and isa
normalconditionofoperation. This1%ofcontaminationfromprecedinganalysesshouldnotbesignificant
enough toaffectquantitationunlessaveryhighconcentrationsample isfollowedbyavery lowconcentration
sample. It isstandard laboratorypractice torunablankafterahighconcentrationsample. Toluene isusedas
arepresentativeof thecarryover in thePurge&Trapsystem; if thecarryover levelofToluene isbelow1%or
0.5ppbon thePIDchromatogram, then itwillnotaffectsubsequentanalyses. (Note: thechromatogramsare
magnifiedforcarryovervisibility).
POPULAR CONFIGURATION GCs
BTEX & Environmental
DELCD Results:
Component Retention Area
TCE
15.750 46.0340
FID Results:
Component
Retention Area
TCE
15.766 58.9100
Toluene
17.566 17.4000
Ethyl Benzene 20.033 51.9080
OrthoXylene 20.833 91.5290
Total
219.7470
PID Results:
Component Retention Area
TCE
15.750 58.1920
Toluene
17.533 4.3400
OrthoXylene 20.850 20.8720
Total 609.1300
(
x
represents the ppb
concentrationofthecarryover)
Determinethecarryoverlevelbycomparing
the areas of the two PIDToluene peaks
resultingfromthesampleandblankruns:
Note: TCE is a contaminant in our factory testing lab.
Sample: cleanwaterblank
