Laboratory Facilities

GC Mass Spec | Flux Chamber | Emissions | Enviro Room

Dr. Lim testing a sample with the Olfactometer.


Odor concentrations are determined using an AC'SCENT International Olfactometer. 

Flow Rate: 20 LPM 
Test Method: Triangular Forced Choice 
Maximum Dilution: 65,000 
Minimum Dilution:  8

Panelists evaluate intensity and Hedonic tone
at recognition and at full strength. 

Intensity is measured on a scale of 0 to 5 where 0 has no perceivable odor and 5 has an extremely strong odor.  Intensity levels are determined by comparing to a reference odorant, n-butanol. 

Hedonic tone is the pleasantness or unpleasantness of an odor.  The scale ranges from -10, extremely unpleasant through +10, extremely pleasant.

Eight trained panelists are used to evaluate each odor sample.  The panelists are required to follow strict rules in order to have their senses in top form.  The panelists are screened following the European Standard (CEN 9805) and using the calibration odorant n-butanol to ensure that no panelists are anosmic (lacking a sensitivity to odor) or hypersensitive.


Gas Chromatograph / Mass Spectrometer


Buoyant and Convective Flux Chamber

The buoyant and convective flux chamber is used to measure and to collect odor and gas emissions from lagoons and other liquid surfaces.


Continuous Emission Monitoring

Analyzers from Thermo Fisher Corporation (TFC), Innova AirTech Instruments (INNOVA), California Analytical Instruments, Thermo Electron, and additional companies are used to measure: 




TFC chemiluminescence, INNOVA photoacoustic infrared

Carbon Dioxide

INNOVA photoacoustic infrared

Hydrogen Sulfide

TFC pulsed fluorescence


INNOVA photoacoustic infrared


Nitrogen Dioxide &

TFC chemiluminescence

Nitric Oxide

Particulate Matter

Tapered Element Oscillating Microbalance (TEOM)

TFC chemiluminescence


The results from the analyzers are fed into a real time on screen computer display.


Environmentally Controlled Room

The environmentally controlled room can be prepared with up to forty 143-L ventilated experiments.  The set-up readily allowed bag sampling for odor, trap sampling for gas chromatography, and continuous emissions monitoring from the adjacent room.




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