Tetra-hydrothiophene ((CH₂)₄S) has an odor that is detectable at very low levels. For this reason, it was included as a component of dangerous gases to allow the detection of leaks by smell. A type of tetra-hydrothiophene gas CRM in the μmol/mol level was developed for the analysis of trace-level odorant gas in natural gas. The gas standards produced simultaneously in 3 bottles and examined by GC-FID were show with 0.12%, reproducibility of preparation and 0.05%, standard uncertainty due to weighing and purity. The concentration of tetra-hydrothiophene ((CH₂)₄S) was 10 µmol/mol level in the cylinder filled with methane, 1500 psi. And the variability of concentration for 1 years was about 0.03% due to the adsorption or instability of (CH₂)₄S. The relative expanded uncertainty of 1.0% (95% of confidence level, k=2) was assigned to the certified value of 10 μmol/mol level of(CH₂)₄S after quantitative evaluation on the purity, mixing, weighing, analysis, adsorption and stability of tetra-hydrothiophene gas.

In this study, the calibration characteristics of six new odorant VOCs along with two reference compound were evaluated based on GC-MS (SIM). For the proper evaluation of the GC/MS method, calibration of 7 VOCs were made both by the SPME and direct injection (DI). The minimum detection limit (MDL) of those VOC determined by SPME method fell in the range of 0.31∼0.38 ppb while those of DI from 6.18∼14.3 ppb. The analytical performance of our SPME/GC-MS method was compared against those tested previously by other study groups. Although more efforts are needed to establish the reliability of our SPME/GC-MS method, the method adapted in this study can be recommended as one of the standard methods for the analysis of the target VOCs in this study to settle formal experiment methods.

In order to classify odors that are in the air at the specific place and at the specific period, it is necessary to generate representative patterns for each odor sources. In this study, in order to classify the various odors efficiently, the k-mean clustering algorithm was applied to the experimental data. Considering the mixed air with various odors, the representative patterns for odor sources were generated with the combination of two or three different odors. As a result, an acquired odor sample could be discriminated and hence its source can be traced by the proposed clustering method, in this study. The results of this study will be useful for settling the civil complaint related odor.

In this study, we used an electronic nose to measure odor intensity and odor quality against an absolute scale. The major feature of this device is that it automatically corrects for differences in sensor sensitivity and smell sensitivity due to odor quality, which allows the intensity of any odor quality to be determined at olfactory sensitivity. In addition to determining the odor intensity as an odor index value, in the standard mode, the device can determine the odor quality by separating and displaying the overall odor on nine category axes (sulfur, amines, organic acids, aldehydes, aromatics, esters, hydrocarbons, hydrogen sulfide and ammonia). This device achieves these results by subjecting the signals from the ten oxide-semiconductor odor-sensor elements to our unique absolute value representation analysis. This study applied electronic nose system of sensor type that can evaluate odor characteristics by real time in leather industry spot and investigated problem that can happen odor sensory method and instrumental analysis method. Also, by evaluation correlation between each measurement method, groped efficient odor evaluation method, and evaluated the effectiveness, Usually, because measurement surrounding and consistency according to measurer"s state of olfactory method are apt to be been lacking, error range is large. If take into account these problem, odor sensor"s result that examine in this research is judged that there is inter-relationship enough with olfactory method result. In comparison between odor sensory test result and instrument analysis result, odor characteristics estimation that can bring synergy effect more than equality in box judge.

Odorous compounds emitted from the melting process for material recycling of plastic have an effect on the sensory annoyance to the nearby residents. The objective of this study was to investigate emission characteristics of malodor in the domestic plastic recycling plants. The olfactometric results showed that the odor concentration among the surveyed plants were significantly different, depending on the melting temperature and material sources. The higher melting temperature led to the higher odor concentration. In particular, as for a plant where melting temperature was 320℃, the odor concentration exceeded 100,000 dilution ratio. However, as the temperature was reduced, the odor emission decreased gradually. This result indicates that reduction of the melting temperature is effective measure to decrease the emission of odor compounds. Quantitative and qualitative analysis of odorous compounds showed that regulatory odor substances such as sulfur compounds, aldehydes and VOCs were found with high concentration in the exhausted gases. Liquid tar in the exhausted gases makes it difficult to remove odorous compounds with traditional odor control devices. In order to eliminate both odorous compounds and liquid tar effectively, a combustion method is strongly recommended in these plants.

The emission characteristics of VOCs (Volatile Organic Compounds) from assembly metal product manufacturing industry (Korean standard industry classification code: 28) were studied. The sampling was carried out at 54 sites in Shiwha-Banwol industrial area with 3 M OVM (Organic Vapor Monitor) #3500 from August to October in 2008. The EPA 8020/8040 (10 chemicals) was used as a standard solution for the quantitative analysis with GC/FID. As the results, the VOCs concentration appeared to range from 0.9 ppb to 22,721.1 ppb, and the average concentration ratio of benzene : toluene : ethylbenzene : m,p-xylene : o-xylene : styrene appeared to be 0.005 : 1.000 : 0.198 : 0.096 : 0.057 : 0.110. Total VOC concentration of the "Manufacture of Structural Metal Products, Tanks, Reservoirs and Steam Generators" (KSIC code: 281) appeared to be seven times higher than that of "Manufacture of other fabricated metal products; metal working service activities" (KSIC code: 289).