Document Dvr9MXN409erMqYDvaYBb8MB5

76 7540 g 91 IC0Q01 DOW CHEMICAL U.S.A. PLAINTIFF'S EXHIBIT OYSTER CREEK DIVISION POST OFFICE BOX BB FREEPORT, TEXAd 775*1 INDUSTRIAL HYGIENE REPORT F EPOPT tVJ. OYC IH-2-I FILE NO. DATE OCD-2-1________ Nay 11, 1976 AUTHOR G. R. Gantt CHECKED date tO/ (97L The chlorine and asbestos exposures of the personnel working in the chlorine production area were surveyed and found to be well within both the existing and proposed exposure standards. This report gives additional conclusions and recommendations as well as the actual co survey information. M&atU >N .MIDLAND G?i Ft8 1 i icc- c. Sereu M. Swank C. VanMetre R. Webb - 0 ,. t.J, > ST0003116 2- - PR03LEM? This study was undertaken to evaluate the exposure of Unit II personnel to asbestos fibers and chlorine. CONCLUSIONS AND RECOMMENDATIONS A. Asbestos ................. 1. Atmospheric concentrations of asbestos fibers were found to be well below the maximum allowable concentration of 2 fibers/cc (TWA) for all operations sampled. 2. The use of disposable coveralls and respirators is good practice and should be continued. 3. A method of asbestos handling and pulping, which eliminates the practice of leaving open bags of asbestos on the cell covers, should be devised. 4. There is too much loose asbestos on the cell covers. This fiber has been wet and probably does not represent a health hazard, but a way should be found to eliminate it. 5. The transfer of bagged asbestos from the warehouse to the cell area is an operation where the potential for overexposure exists. The use of asbestos in polyethylene lined bags seems to have reduced the possibility of overexposure and the use of this type bag should be continued. 6. Training programs on the hazards of and proper handling techniques for asbestos appear to be very good. B. Chlorine 1. Atmospheric concentrations of chlorine were found to be below the maximum allowable concentrations (TWA of lppm) for all areas. ST0003 117 hI ST0003117 ST0003I I 3 -3- 2. The highest concentrations of chlorine were found in the secondary chlorine compressor area. 3. No suitable method for determining the peak exposure to chlorine has been found. Unit II personnel have been advised to use respiratory protection at the first odor of chlorine. PROCESS Unit II produces chlorine and sodium hydroxide by the electrolysis of sodium chloride brine. The electrolysis is carried out in Dow diaphragm cells which utilize an asbestos on wire screen diaphragm to separate the anode and cathode compartments. During the operation of those cells, holes may develop in the asbestos portion of the diaphragm. Such holes are undesirable since they effect both the performance and longevity of the cells. To plug these holes, a slurry of asbestos in water is added to the anode compartment of the cell. This procedure is known as "pulping" and involves the following steps: a. A bag of asbestos is carried from the cell area storage location to the top of the cell torbe pulped. b. The bag is opened and the dry asbestos is wet with a hose. c. The asbestos is dumped from the bag into a large plastic basket where it is slurried with water. d. The slurry is added to the cell through a large funnel. e. The area is washed thoroughly with a hose. The major portion of the asbestos is stored in a warehouse which is some distance from the cell area. It is moved to a temporary storage location in the cell area by use of a forklift. This temporary storage area will hold about a week's supply of asbestos. The chlorine which is produced in the cell area is collected under a slight vacuum. It is dried and goes through successive stages of compression and cooling until the pressure reaches a level at which the chlorine can be readily transported. ST0003118 S T 0003I19 -4- DISCUSSION Two job classifications were under study during the course of this study. The cell control technician (operator) is responsible for the day to day operation of the electrolytic cells. He generally works a straight day schedule. During the course of this work he is on top of or around the cells for several hours a day. He may handle asbestos every day, but the amount of time spent moving asbestos bags and pulping seldom exceeds thirty minutes and is frequently much less. All technicians who handle asbestos wear disposable coveralls and mouth bit respirators while doing so. The short lengths of time during which asbestos is actually handled gives an actual TWA exposure of far less than the concentrations given for pulping operations in Table I of the Data Section. The chlorine technician is responsible for the operation of the chlorine cooling, drying and compression areas. During the day, he nay also assist the cell control technicians. He works a rotating schedule (shift) and at night he is responsible for the operation of the cells. The asbestos samplinq covered only the cell control .technicians. They were considered to be the most frequently exposed group because they handle asbestos almost every day. The chlorine survey included both job classifications and all chlorine manufacturing areas. Overexposure to asbestos fibers can cause asbestosis (a disabling injury in which scar tissue forms in the lungs) and has been implicated in the formation of tumors of the chest cavity. The currently recommended maximum exposure is 2 fibers/cc for an eight-hour time weighted average (TWA). Chlorine overexposure can be divided into two caragories. An acute overexposure, such as could occur during a gas release, can lead to possible lung damage and death. A chronic overexposure can lead to irritation of the respitatory system producing a condition which has been referred to as a "chlorine cold". The maximum allowable concentrations are a TWA of 1 ppm and a ceiling level of 3 ppm. At any concentrations above the ceiling level, respiratory protection . should be used. CAMPLING AND ANALYSIS A. Asbestos The samples being reported were collected during June, 1975 and January, 1976. Breathing zone samples ST0003119 ST0003!20 -5- were collected in the warehouse area and the cell area while asbestos was being handled. Technicians also wore personnel monitors while performing those portions of their jobs which did not require the handling of asbestos. These samples were collected to insure that there was no contamination of the work, area from the adjoining temporary storage area. Area samples were collected in the storage areas to insure that levels there were not excessive. Samples were collected on a Millipore 37 mm filter cassette having an exposed area of 855 sq. mm. A Bendix Micronair or MSA Model S sampling pump set to a flow rate of 1.7 to 2.0 1/min. was used to pull air through the cassette. Flow rates were measured with an American Meter Division Model 115 Dry Test Meter. The fiber counts were obtained by. the Microscopy Section of the Texas Division Central Laboratory. B. Chlorine The chlorine samples were collected on a bed of activated charcoal contained in a Pyrex drying tube. The sampled air was pulled through the charcoal bed with a Bendix Micronair or MSA Model S sampling pump set to a flow rate of 2 - 2.3 1/min. Flow rates were measured in the same manner as those for asbestos sampling. All chlorine samples were of the area type rather than personnel monitors. The decision to monitor in this fashion was wade for the following reasons: 1. Having a personnel monitor with a glass sampling tube was considered unsafe. 2. While a personnel monitor gives information about exposure levels it does not provide information about the location(s) where the exposure actually occured. For any type of job where there is a considerable amount of movement from place to place this is a necessary piece of information. The measurement of the chlorine levels is based on the catalytic properties of the charcoal bed which converts chlorine to chloride ion. The chloride ion is extracted from the charcoal and titrated with silver nitrate. The titrations of these samples were performed by the Texas Division Central Laboratory using a coulometric method of end point detection. c- ST0003120 6- PRESENTATION OF DATA Table I presents all the areas sampled and the results of these analysis. Also included is additional information such as total amount of air sampled and total fiber counts. Table II presents information about the chlorine sampling and results of the analysis of these samples. Table III shows how the information from Table II is used to determine a composite average concentration for various areas of the chlorine manufacturing facility. Tabic IV is a compilation of actual time spent in each area which, when combined with the composite average concentrations, leads to the TWA exposure listed. Figure I is an overview of the chlorine manufacturing facilities and areas surveyed. The circled letters represent the areas described in Table III. ; I* ST0003121 ST0003!2 I w r-1 s! Z| o H <1 Ui "si ffl C d1 to oU W +J -tHw rH 'V c a 01 o -Q >H w0d n u-4 o cr c JZ <y cou H Id T3 nj W O' :* O a a X> *ch rH v u c co c *w *o Id o cd W W w (/) HHH O H H H J a) CH (0 03 CU Ol Dj m Cl H H H lU mdddo o3 Pi cu 04 2: r-f H (1) O C rH w oXT iOUc to CUJ Q) o X> (0 h J h 0 to 0> oj q a c 03 2 10 40- to o jQ to fl3 x: 4J H 0 to d 0 JC 03 u 03 3t T3 C rd TJ <D to o rH u to >H o o X3 4J c a) u 0) M o C in o o CP H id X) Q i cO' <D -n to 0 l-i m w 0 n 3 T3 0 4J T> C p to >.0/0 to 0 rH O X 0J X) ri O XI to 03 U O w 03 D a c fO x <w P O H S O' P x o-h O *H rH to r* 3 *0 o O C +J >,0/0 tO H ox w rH O J3 10 VH o to a ac to w tn w HH H HHH o a> o uo o O' o> tr* GGC HI *H *H cua a HHH dd d aaa . rH fN fO V IO VO i * ' O rH CM 00 CT\ HrIH % +-AJ\ - .'V`.v> IO >' iy /. o \-nrn : V.;: ST0003122 TABLE II CHLORINE SAMPLING LOCATIONS AND RESULTS 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 19. 19. LOCATION AIR PUMPED IN 1 . Cell covers - Series I Cell covers - Series 3 792 702 Cell covers - Series 4 Cell covers - Series 6 Cell covers - Series 5 Cell covers - Series 7 Ground level between Series 5 and 8 828 720 736 640 805 Ground level between Series 1 and 4 700 South end of Series 8 817 Chlorine Scrubber Deck Near Chlorinated water pump 840 1053 North Side - Sump 1 920 Between C-202 A/B 810 (secondary chlorine compressor) Between C-203 A/B 780 (secondary chlorine compressor) North Side of Terry Turbine (primary compressor deck) South Side of Terry Turbine (primary compressor deck) 897 840 South Side of T-202 (drying tower) 966 Between C-203 A/B 870 (secondary chlorine compressors) Cell Lab 1000 TOTAL uq OF Cl~ FOUND 385 151 743 491 568 518 34 2 CHLORINE 0 IN ppm 0.17 0.07 0.31 0.23 0.27 0.28 0.15 52 6 0.26 835 29 533 0.35 0.01 ' 0.17 771 743 0.29 0.32 2177 0.96 1143 0.44 108 0.05 121 1183 0.04 0.47 90 0.03 ST0003I23 9-15-76 ' Bi mir jri* ST0003123 ST0003 I 2U ST0003124 H fQ O w o a m \o CD xe H rH rH wa a OO O , nj n H T3 C -U rj -H CT- u U ^ U "T3 --1 c H -H lj c H H C 0) C -H 7 W S rH o u Ha 0 TD x: x: .h _ O H E V. ID C1 2 O M 14 -M C E-* <y x: 0) o Eh TD C G (/ -rH O n> v c W 0 c c/> C rH O </> 03 O u H rH *-H 0) U 4J 0W xH: *^h H -U 3 > U CC O ooo HUrt DUC >"5 o O^ u V) w ra 23 Eh e o M <M c o iH M ro c 0) u c o u (1) c H u o H ,C o tj> c H t/> ST0003I 25 u> tol rH I Ol ST0003125 FIGURE I CHLORINE MANUFACTURING AREA r- Not drawn to scale 9-15-76 Main Building, Shop, Offices, Etc. i i f -r ST0003126