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IPN 074-397-P1G
HAPSITE Smart Operating Manual
13.2.5 Making the Measurement
To make a measurement using the HSS, a method is required. To quantify the
analytes detected, a calibrated method is required.
Once the calibrated method is completed, samples may be analyzed and
compared to the calibration for quantitative analysis. Sample analysis must be
performed using the same procedure used to perform the calibration runs.
Refer to Chapter 11, Method Editor and Chapter 12, Target Compound Methods
for additional information on developing methods and calibration for quantitative
analysis.
13.3 Maintenance of HSS
Other than replacement of consumable items, most maintenance will involve
routine purging of the system as needed when analyzing high concentration
samples, needle replacement, or cleaning of the sample wells. Refer to section
15.10, Replacing the HSS Needle, on page 15-51.
13.3.1 Clean Out after a High Concentration Sample
When high concentration samples are analyzed using the HSS, the system can
retain analytes which will be detected if the next sample has low levels of those
compounds. This is typically referred to as a carry-over contamination. Carry-over
contamination can be reduced to approximately 0.1% by using Purge. In the case
of severe carryover, use the Flush function.
13.3.1.1 Purge Procedure
To purge the HSS, run a blank with the HSS needle in a clean, empty purge vial.
In some cases, the blank may need to be run more than once.
HINT: A blank is the same method run without introducing a sample.
13.3.2 Cleaning Up a High Background
High background is usually encountered because some compounds are retained
in the HSS or the HAPSITE. This could be in the HSS valves, transfer line, or within
the HAPSITE.
To test whether the background is in the HSS or the HAPSITE, disconnect the
Transfer Line, connect the air sampling probe to the HAPSITE, and analyze a clean
air sample. If the contamination is no longer present, the contamination is in the
HSS or Transfer Line.