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IPN 074-397-P1G
HAPSITE Smart Operating Manual
Chapter 13
Headspace Sampling System
13.1 Introduction
The Headspace Sampling System (HSS) is an accessory to the HAPSITE portable
GC/MS, allowing testing for Volatile Compounds in various solid and liquid
matrices, including soil and water. Used in combination with the HAPSITE, the
Headspace Sampling System attachment provides the opportunity to perform soil
and water analyses for quantitative and qualitative results in the field. See Figure
13-1.
Figure 13-1 Headspace Sampling System
The HAPSITE is designed to analyze volatile compounds in air, so samples must
be introduced in a gas phase. HSS technology involves heating samples of soil or
water, in a closed sample container, to a known temperature. Heat forces the
volatile components to partition between the sample and the headspace above the
sample. After allowing sufficient time for equilibration to occur, a portion of the
headspace (now containing volatile compounds from the sample) is introduced to
the HAPSITE as a gas sample.
Unknowns are tentatively identified using the National Institute of Standards and
Technology (NIST) mass spectral library and known compounds can be quantified
using a prepared calibration curve. This is accomplished using the combination of
the HAPSITE’s Gas Chromatograph (GC) and Mass Spectrometer (MS) in the
same as air sample analysis.