Analytical Services

ASTM D1946 & EPA 25c/3c – Fixed Gases and TNMOC

An evacuated stainless-steel canister is used to collect the sample.  A sampling probe is punched into the landfill cap and a canister is attached to a sample line extending from the probe.  The canister vacuum then draws in gases generated by the landfill through a flow controller. The canister is pressurized with helium in the laboratory prior to analysis.

For analysis the canister is attached to our custom analytical instrument and a sample loop is filled with sample.  On injection the sample is swept into a GC.  Using a series of valves and the method required Unibead/Carboseive G columns, methane and carbon dioxide are allowed to elute from the columns, after which the remaining sample is backflushed, oxidized and reduced to methane to be detected by the flame ionization detector as one chromatographic peak.  Simultaneously, a second sample loop is injected and analyzed by the thermal conductivity detector for the quantification of nitrogen and oxygen.

Air Technology provides the expertise and experience needed to accomplish the difficult task of analyzing sulfur compounds in both parts per million and parts per billion range.  Following the procedures described in EPA Methods 15 and 16, the sample is introduced into a GC that is equipped with a flame photometric detector.  The chromatography is performed on a capillary column or specially packed Teflon column to minimize interactions with the compounds of interest.​

EPA T03 – Petroleum Hyrdrocarbons

In support of investigation or remediation activities at underground fuel tank sites, AirTECHNOLOGY provides the expertise to meet the strictest requirements, and the capacity to handle large or small sample loads for the analysis of benzene, toluene, ethylbenzene, xylenes, methyl tert-butyl ether, hexane and total volatile petroleum hydrocarbons.​

Samples are usually collected in Tedlar bags by pumping soil vapors or ambient air into the bag.  Due to the relatively short holding time associated with Tedlar bags (three days), the samples are rushed to the laboratory for analysis.

ASTM D1945 – Natural Gas

Air Technology has extensive experience in the analysis of natural gas or refinery gas.  Samples are collected in stainless steel canisters, which are then analyzed by GC/FID/TCD.  The analysis determines the concentration of several hydrocarbon species from which it can then calculate a BTU and specific gravity.

Siloxanes

RSKSOP-175 – Dissolved Gases in Water

Natural attenuation, or intrinsic remediation, is increasingly becoming the remediation technique of choice.  This technique allows for naturally occurring microbial activity to metabolize the contaminants of concern.  The suitability of a site or progress of the remediation is evaluated partly on results of the analysis of groundwater samples for dissolved gases such as methane, ethane, or ethylene.​

Air Technology provides this unique analytical procedure.  The procedure requires that the sample be collected in an airtight container (typically a 40-mL VOA vial) preserved to pH 2 (unless carbon dioxide needs to be determined).  The laboratory generates a headspace in the sample by replacing a portion of the water with helium.  After thorough agitation and equilibration, an aliquot of the headspace is analyzed via GC/FID.  Henry’s Law stipulates that, in a closed system in equilibrium, the concentration of a gas in the headspace can be used to determine the concentration of the gas dissolved in water.

Hydrocarbon Speciation

Ozone is of primary concern to the USEPA in its latest promulgation to the Clean Air Act, especially ozone’s presence in metropolitan areas.  The emission of hydrocarbons (ozone precursors) from vehicles and industrial sources is the leading cause of man-made production of ozone.