Volatile Organic Compound Testing (VOC) Services
Organic determination is a very extensive field in air emission testing. Often, the sampling and collection techniques are far more important than the laboratory analyses, and have a larger impact on the final results. Entech Engineering's personnel specializes in this area and have had extensive experience designing and conducting organic testing. Please contact us to discuss your particular problems and needs.
- Gaseous Organic Analysis Using GC/FID (RM 18) - For determination of gaseous organic compounds, a gas chromatograph equipped with flame ionization detector (GC/FID) is used to measure the organics, either on-line or as grab samples. Separation of the organic species is conducted by selecting the appropriate column for separating the compound of interest from the sample matrix. The analysis is conducted by experienced chemists or GC operators according to the procedures described in the EPA Reference Method 18.
- Volatile Organic Sampling Train (VOST) (EPA Method 0030) - Although the sampling principle for a VOST is similar to the RM 5 train, the VOST is designed to collect a small volume of samples while the RM 5 train is designed for bulk sampling. The VOST train collects VOCs on sorbent tubes containing Tenax or other adsorption polymers. VOC samples are sealed and transported to the laboratory where they are desorbed, either thermally or by the purge-and-trap method. Analysis is usually conducted using a gas chromatograph (GC) equipped with various detectors or mass spectroscopy (GC/MS)
- Modified Method 5 for Semivolatile Organics (EPA Method 0010) - A modified Method 5 train is an RM 5 train modified to include a condensing unit with an XAD-2 sorbent trap. This method is used to collect a large volume of flue gas samples, i.e., more than 100 cubic feet, for the determination of heavy or semi-volatile organics with boiling points above 120ºC. Organics collected on the XAD-2 are usually recovered using a solvent wash and analyzed by GC/MS. This method is used to determine many semi-volatile organic concentrations including dioxins and furans (as in Reference Method 23).