Document 8Vbkay1ede3RyEL2Dr4683GBd

INDUSTRIAL HYGIENE SURVEY GENERAL CABLE CORPORATION MEMPHIS, TENNESSEE INTRODUCTION M & M Protection Consultants retained George D. Clayton & Associates to conduct an industrial hygiene survey of the General Cable Corpora tion extrusion plant located in Memphis, Tennessee. Purposes of this study uere to determine concentrations of vinyl chloride to which workers were being exposed and to interpret the results in terms of potential health hazards, with particular reference to regulations promulgated under the Occupational Safety and Health Act of 1970 and other accepted standards of good practice within the field of occupational health. Results of the survey, conducted on May 16, 1974 by Mr. Michael S. Mosher of Clayton & Associates, are reported here in. DESCRIPTION OF OPERATIONS The General Cable Corporation employs approximately 100 people at their Memphis, Tennessee Plant in the manufacture of extruded wire products incorporating polyvinyl chloride (PVC). Raw PVC is mixed with dibasic lead phthalate in a dry blend room, which is a regular work station for only one man. An exhaust hood is used at the weigh area but there is no local exhaust ventilation where the lead is dumped into the hot (250F) mixer with the PVC. The mixture is then transfered from the hot to the cold (room temperature) mixer, from which the mixture is transferee: to bins by means of a conveyor. The mixed PVC is allowed to free-fall from the end of the conveyor into open bins. The extruders, which are fed from the bins containing polyvinyl chloride by a pumping mechanism, operate at approximately 425F. Metal wire is pulled through the hot extruders and then through a water quenching operation in a trough located within a foot of the extruder head. From the end of the trough the coated wire is wound and packaged. The regular domestic sources of PVC were in use during the survey. DISCUSSION OF POTENTIAL HEALTH HAZARD ASSOCIATED VITH EXPOSURE TO VINYL CHLORIDE Vinyl chloride is a gas at standard conditions. Until very recently the material was considered to be much more of a fire and explosion hazard than a health hazard. Although vinyl- chloride was known to be anesthetic at relatively high concentrations (16,000 ppm) there vas no evidence of a significant hazard associated with exposures of workers to concentrations normally encountered in industrial situations of manufacture and use. BFG26301 23559003 -2- However, in January, 1974 , the B. F. Goodrich Company rep.iicd that four of their employees at the Company's plant in Louisville Kentucky, had died of liver angiosarcoma, a cancer apparently re lated to their past exposure to vinyl chloride. As a result; of this report and subsequent investigations by the National institute for Occupational Safety and Health and the Occupational S<ii'cty and Health Administration, the acceptable limit for concentrations cf vinyl chloride in air to which workers could be exposed v;i<i reduced by an emergency temporary health standard established by t |<L. jj.s. Department of Labor on April 5 , 1974 , from a ceiling of 5tii) ppm to a ceiling of 50 ppm. Continuing studies with animals, and comprehensive epidem!,, 10gicai studies of vinyl chloride and polyvinyl chloride workers, Indicate that exposure to concentrations as low as 50 ppm are capably cf producing adverse effects. Accordingly, the U.S. Department 0f Labor has proposed a permanent health standard limiting w<ti-iler exposures to "no detectable level" using methods capable m' measuring one part per million with an accuracy of plus-or-minus 50 percent. SAMPLING AND ANALYTICAL METHODS Air sampling conducted during this study was of two basic types: general area and personal breathing zone. For both types, samples were collected by drawing air through small glass tubes, packed v.'ith activated carbon, at a measured flowrate by means of small batteryoperated pumps (Mine Safety Appliances Company, Model G). The general area samples were collected at stationary situn strategically located through the work areas. The personal breathing zone sampling units were worn by the workers; the pump was attached to the belt and the sampler head (activated carbon tube) u,,s attached on the outside of the worker's shirt in the approximate bv,,athing zone. Thus, these latter samples were representative of ti,0 con ditions to which the worker was exposed during the sampling period. After collection of the sample, the glass tubes were sealed vith small plastic caps for transfer to the Clayton & Associate^ labora tory. All samples were analyzed subsequently using gas chromato graphic techniques. These analytical results, in conjunction with the sampling data (air flowrate and duration of the sampling to yield the total volume of air sampled) were used to calculate the corresponding concentrations of vinyl chloride in terms of parts of vinyl chloride per million parts of air, by volume. r PRESENTATION OP RESULTS The results of the vinyl chloride sampling in the personal breathing zones and general areas of the operation are presented in Tables I and II, respectively. Examination of these data shows that no detectable amount of vinyl chloride was observed in any of the samples collected. The limit of detection for the combined sampling and analytical methods was 0.04 ppm, or less. / 23539004 BFG26302 -3- COKCLUSION On the basis of observations and measurements made during this survey, it is concluded that the concentrations of vinyl chloride to vhich workers are exposed during the course of routine operation of the plant are within acceptable limits. In all areas, concen trations were less than 0.04 ppm, considerably less than the cur rently acceptable ceiling concentration (50 ppm) established by the U.S. Department of Labor's emergency temporary standard and the proposed permanent standard of one ppm. This report Hichael S. Mosher, Industrial Hygienist 23359005 BFG26303 BFG26304 o o o G eneral C able C orp. TABLE I GEORGE D. CLAYTON & ASSOCIATES INDUSTRIAL HYGIENE SAMPLING SUMMARY 1 BFG26305 o o c o N