Instruments
GCMS
&
TEOM
WHAT is GCMS? - GCMS stands for Gas
Chromatography-Mass Spectrometry. It is an instrumental means of separating and
positively identifying and quantifying compounds.
HOW does it work?
- The GCMS that Emission Monitoring employs for testing works by sampling gases
directly, separating the various components contained in the sample from each
other using the GC, and identifying positively the separated compounds using a
mass spectrometer. The results from each ten-minute run are analyzed within
minutes of completion, with results provided on-site. We have found that
providing on-site results to our clients adds a dimension to testing services
that is unsurpassed. It enables important decisions to be made that would
previously have taken weeks because of off-site laboratory analysis.
Additionally, we have found that our clients are absolutely thrilled when they
receive their results before we leave the test site.
WHAT are the
applications of GCMS? - GCMS testing has been conducted at numerous
stationary sources; foundries, mineral calciners, cement kilns, lead smelters,
reciprocating engines and turbines. In addition, we have conducted testing at
ambient sources and various emission points of industrial processes. In certain
circumstances, we have analyzed Tedlar bag and canister samples when sampling
directly was impossible. The very low achievable detection limits of the
technique make it particularly attractive for ambient sampling because the need
to concentrate the sample on adsorbent media is not necessary. For example,
benzene toluene and xylene compounds (BTX) can be detected and quantified
positively at concentrations approximating 10 part per billion. Collection and
analysis of these compounds by traditional methods usually provides for
detection limits of 1 part per million or greater.
WHY is this GCMS
testing service Unique? - On-site GCMS testing is unique because, in the
past, a GCMS was a big as your living room, and required a couple of scientists
to operate and maintain. That's why sampling and analysis using mass
spectrometry usually is performed in a laboratory, and takes from one week to
one month to get the results. The HAPSITE GCMS was designed and manufactured to
be fully portable. The GCMS weighs only 35 lbs. and is fully operational when
mobile. This allows the technique to be utilized in a manner that was never possible
until now. The technique requires a great deal of operator knowledge and
experience with operating a GCMS.
WHAT Compounds
can be Analyzed for Using GCMS? - Technically, compounds that have a
molecular weigh between 44 and 300 can be analyzed for in combustion source
effluent. Ambient applications can afford a lower molecular weight range of
analysis. In general, the rule of thumb for this particular GCMS is that we can
analyze volatile compounds (not metals or dioxins) with vapor pressures in the
range from hexane up to naphthalene. We would be happy to discuss specific
applications on a case by case basis. We typically calibrate for over 30
compounds, but the potential applications for analyzing volatile compounds are
virtually unlimited.
TEOM
TESTING SERVICES - NEW
EMI has recently acquired an inertial microbalance for in-situ
particulate matter testing. The TEOM can
provide real time measurement of PM for a wide range of applications including
compliance testing by M5 and M17, PM control device tuning and diagnostics, as
well as calibration of PM CEMS.