Document pexjgpvLnx07ryegpLzXn353w

UNION CARBIDE PLANT LABORATORY R* N. .WHEELER, JR, UNION CARBIDE CORPORATION CHEMICALS AND FUSTICS SOUTH CHARLESTON PLANT P.O.BOX 6004 SOUTH CHARLESTON, W.VA. 2 5303. VINYL CHLORIDE MONOMER THRESHOLD ODOR CONCENTRATION IN AIR SUMMARY As the result of some discrepancies existing in the literature 1,2, for the Threshold Odor Level of vinyl chloride monomer in air, a study was initiated by the South Charleston Plant Odor Panel to determine the lowest detectable odor level of VCM in air. These data are tabulated in Table I. DISCUSSION A series of six samples of vinyl chloride monomer and a blank were presented to the odor panel for deter- mination of the Threshold Odor Level. The samples were prepared in increasing concentration over odorless distilled water in 250-ml Erlen- raeyer flasks with stainless steel caps and submitted to a panel of seven people with instructions to record the first detectable odor. Each panelist tested the samples individually, so that there was no collusion among panelists. A sample of the VCM vapor was then taken and analyzed by an AID Gas Chromatograph Model 511, hydrogen flame detector equipped with an 8 ft. column packed with Poropak Q 50-80 mesh. These data were corrected for the water vapor pressure and calculated to normal gas volume conditions, 0C and 760 mm mercury. The tests and analytical data were duplicated. CONCLUSION Individuals vary greatly as to the minimum concentration which is barely detectable. Our most sensitive odor panelists barely detected an odor of VCM at 1200 ppm. Normal odor detection level of VCM is at 2000 ppm. The normal detection level of VCM for the average untrained person is probably higher than 2000 ppm. An explanation as to why discrepancies have existed in the Threshold Odor Level is the fact that VCM is now a much purer commercial product than it was years ago and the odor detected was probably due to some impurity rather than VCM. Chairman South Charleston Plant Odor Panel UCC 092728 UNION CARBIDE aecm'ro PLANT LABORATORY JUL 05 * N* jr. UNION CARBIDE CORPORATION CHEMICALS AND PLASTICS SOUTH CHARLESTON PLANT P.O.BOX 8004 SOUTH CHARLESTON, W.VA. 2S303 TABLE I THRESHOLD ODOR LEVEL OP VINYL CHLORIDE MONOMER IN AIR VIny1 Chloride Monomer in Air ppm______ Blank 133 350 680 1200 1960 3800 Number of Panelists that Detected VCM Odor i 0 0 0 0 *2 7 7 ucc 092729 RECEJVFD UNION CARBIDE JUL 05 1974 PLANT LABORATORY R. N. WHEELER, JR, UNION CARBIDE CORPORATION CHEMICALS AND PLASTICS SOUTH CHARLESTON PLANT P.O.BOX 8004 SOUTH CHARLESTON, W,VA. 25303 REFERENCES 1. SDE-56 Vinyl Chloride Issued 1972 Page 6, Paragraph 3.1.2. Manufacturing Chemists Association Threshold Odor 260 ppm 2. Industrial Hygiene and Toxicology Patty, F. A. and Associates Interscience Publishers 1962 Volume 2 Page 1304 4100 ppm lowest level VCM odor can be detected. 3. Basic Principles of Sensory Evaluation STP 433 American Society for Testing and Materials 4. Manual on Sensory Testing Methods STP 434 American Society for Testing and Materials 5. Correlation of Subjective-Objective Methods in the Study of Odors and Taste STP 440 American Society for Testing and Materials UCC 092730 UNION CARBIDE PLANT LABORATORY RECp/v D ML Os m UNION CARBIDE CORPORATION CHEMICALS AND PLASTICS SOUTH CHARLESTON PLANT P.O.BOX BOCM SOUTH CHARLESTON, W.VA. 3V.I03 VINYL CHLORIDE MONOMER THRESHOLD ODOR CONCENTRATION IN AIR The Odor Panelists have been screened for proficiency by the Arthur D. Little, Inc., Co. and have an average of 10 years experience in odor detections and evaluations. These screening test results are on file in the South Charleston Plant Laboratory. Mr. Griffith, the chairman and moderator of the testing program is a graduate chemist and a member of the American Society for Testing and Materials E-18 Committee. This committee was founded in 1960 to promote knowledge, stimulate research, state principles and develop recommended practices in all areas of sensory evaluation of materials and products. Fields of interest currently represented include air pollution, clothing and textiles, metals and appliances, beverages and liquors, manufactured food products, flavors and fragrances, agricultural commodities, naval stores, tobacco, chemicals, paints and varnishes, paper and plastics, telephone, railroads, petro leum and allied products, laboratory equipment, packaging materials and pharmaceuticals. He is currently co-chairman of a Task Group to develop a recommended practice for odor of chemicals. Mr. Griffith represents the Kanawha Valley Union Carbide Locations on this committee. MAA/jjh ji. A. Aitken " Director of Laboratories Ucc 092731