Document MGKgaqjRNXaObrrDNqgoVkQpx

DOW CHEMICAL U.S.A. April 8, 1985 LOUISIANA DIVISION P. O. BOX ISO PLAQUEMINE. LOUISIANA 70765-0160 BOA 388-8000 Cy Barrios Plant Superintendent CPE cc: Dr. M. Currier 3. Granier B. Ledford A. Seidule B. Shamburger CPE INDUSTRIAL HYGIENE SURVEY, 1984 Summary: The employees that had a likelihood for exposure in their Jobs to chlorine, dust, tetrahydrofuran and noise were monitored using approved sampling and analytical methods. Personnel samples that were obtained on the Outside S.O.T. and Day Maintenance operators indicate a problem with instantaneous exposure to chlorine. Area samples of the plant have traced the source of the chlorine exposures and plans have been made to install engineering controls as soon as possible. Operators' potential exposures to dust, tetrahydrofuran and noise were below current exposure guidelines. Conclusions and Recommendations: 1. Instantaneous exposures to chlorine that were detected on outside S.O.T.'s and Day Maintenance operators averaged 2.1 ppm amd 8.1 ppm respectively. The OSHA Permissable exposure limit is a 1 ppm ceiling limit. Area samples of the plant have traced the source of the chlorine exposures to the water that is being discharged into the drainage ditch from the wash column's static screens during reactor transfers. The plant's current plans are to develop and implement engineering controls for neutralizing the residual chlorine in the water, before it is discharged into the ditches. The operators have been informed of the problem and of the areas where chlorine has been detected. 2. Operators' potential exposures to dust while operating the bag slitter and housekeeping in the weigh feeder room, were lower than the Exposure Guidelines for the additives in use. It is recommended that dust masks continue to be required for these Jobs to control exposures to dust as low as possible. AN OPERATING UNIT OF THE DOW CHEMICAL COMPANY DO 105710 CONFIDENTIAL CPE Industrial Hygiene Survey, 1984 April 9, 1985 Page 2 3. Operators' exposures to Tetrahydrofuran, while performing pH tests on CPE resin, were below the Exposure Guideline. The solvent is used under a fume ventilation hood and the results of the personnel samples indicate that this is adequate for controlling exposures. 4. Area noise surveys of the plant did not reveal any significant changes in noise levels. The high noise areas (<90 dbA) of the plant are properly posted with ear protection warning signs and the location of these areas will be communicated to operators in the annual Industrial Hygiene meetings. CHLORINE EXPOSURE EVALUATION Explanation of Guidelines and Sampling Method The OSHA Permissable Exposure Limit (PEL) for chlorine is a 1 ppm ceiling limit. A ceiling limit is the concentration that a person should not be exposed above for any period of time. The personnel samples were obtained from the operators breathing zones and represent as nearly as possible actual exposures. A chlorine direct reading dosimeter with a "Wolcott" Nafion membrane type sensor was used to obtain the personnel samples. The dosimeter stores the highest instantaneous reading that was detected for the duration of the sample. Other data storage capabilities are the highest 15 minutes average concentration, the average concentration for the duration of the sample, and the elapsed time from the start of the sample. Calibration of dosimeters was performed by the Division^ Industrial Hygiene Department using a Metronics Dynacalibrator. All of the dosimeters and probes were calibrated before and after each sample with a known chlorine concentration of 1 ppm (vol,vol). The area samples were obtained using the same sensor, but the data was collected and stored using a metronics datalogger. The datalogger was advantageous for these type samples due to it's capacity to store individual 30 second values. DO 105711 CONFIDENTIAL CPE Industrial Hygi ne Survey, 1984 April 9, 1985 Page 3 1. Personnel Monitoring As shown on Table 1 (Attachment 1), of the six (6) samples that were obtained on the Day Maintenance and Outside S.O.T. jobs; five (5) were above the OSHA PEL for chlorine. The highest exposure detected was in the Day Maintenance job and equalled greater than 12 ppm for the highest instantaneous reading, 1.27 ppm for the highest 15 minute average, and 0.11 ppm for the sample duration of 261 minutes. The average concentrations that were detected in both jobs are as folows: Time Weighted Nunber 15 Average for of Minute Sample 3obSamples Instantaneous Avq. Duration Day Maintenance 2 8.07 ppm .67 ppm .05 ppm Outside S.O.T. 4 2.12 ppm .01 ppm .00 ppm 2. Area Monitoring The area samples indicate that chlorine is being released from the water in the drainage ditches during reactor transfers. As shown on Attachment 2, the highest concentrations (3 - >16 ppm and 16 - >20 ppm) were detected near the wash columns on each train. Apparently the water that is transferred over from the wash column static screens contains residual chlorine and this is released as the water cools going to the drainage ditch. All of the concentrations that were detected dissipated rapidly. DUST EXPOSURE EVALUATION Explanation of Guidelines and Sampling Method The dust that operators may potentially be exposed to in $he weigh feeder room or at the bag slitter are non-asbestos talc, calcium carbonate and CPE resin. The American Conference of Governmental Industrial Hygiene (ACGIH) Threshold Limit Value (TLV) for non-asbestos talc is 2 mg/m^ respirable dust. The TLV for nuisance dust such as calcium carbonate and CPE resin is 10 mg/nr total dust or 5 mg/nr respirable dust. TLV's are exposure guidelines for a normal eight-hour workday and 40 hour work week. Both of the jobs that were monitored were relatively short-term jobs lasting from 16 to 180 minutes, but may be performed several times a day. ACGIH recommendations for short-term exposures are as follows: "Short-term exposures should exceed three times the TLV-TWA for no more than a total of 30 minutes during the workday and under no circumstances should they exceed five times the TLV, provided that the TLV-TWA is not exceeded." DO 105712 CONFIDENTIAL CPE Industrial Hygiene Survey, 1984 April 9, 1985 Page 4 A Gilian Hi Flow Air Sampler with a Bendix midget cyclone and matched weight filter cassette was used to obtain breathing zone samples from operators working in the weigh-feeder room and at the bag slitter. The samples were analyzed gravimetrically for respirable and non-respirable dust. 1. Personnel Monitoring Because a dust mask is required to be worn when working in the weigh feeder room or operating the bag slitter, the concentrations that were detected are potential exposures. Table 2 (Attachment 3) lists the results of the excursion samples that were taken on the housekeeping Job in the weigh feeder room and the bag slitter Job. The highest concentration that was detected on the housekeeping Job was 3.5 mg/m3 respirable dust and 10.6 mg/m3 non-respirable dust for 16 minutes. The highest concentration that was detected for the bag slitter Job was 4.1 mg/m3 respirable dust and 1.4 mg/m3 for non-respirable dust for 41 minutes. The following are the average concentrations that were detected for all of the samples: Number Respirable of Dust _______ Job__________ Samples______ (ing/m3) Housekeeping 3 2.2 Bag Slitter 5 2.9 Total Dust (mg/m3) 8.6 6.1 NOISE EXPOSURE EVALUATION Method and Explanation of Guidelines ** The new Dupont MK-2 Audio Dosimeter was used to measure employee's exposure to noise and was also used as a sound level meter to measure area noise levels. The dosimeter meets or exceeds all current requirements established by government agencies in the United States for personal audio dosimeters. All noise measurements were made using an 80 and 90 db(A) threshold level and a 90 db(A) criterion level. The threshold is the level that noise must exceed to be included in the dose calculation and the criterion is the decibel level that will yield a 100 percent dose in eight hours. The 90 db(A) criteron level is an 0SHA regulation, to obtain the dose percent using the Louisiana Division criterion level of 85 db(A) the results were multiplied by two (2). This is true due to the 5 db(A) doubling rate that is included in both the 0SHA regulations and the Louisiana Division Standard. All of the audio dosimeters were calibrated before and Audio Dosimeter Calibrator) at sound levels of 94 and 114 decibels. 00 105713 CONFIDENTIAL CPE Industrial Hygiene Survey, 1984 April 9, 1985 Page 5 1. Personnel Monitoring Because ear protection is required to be worn in the high noise areas of the plant, the noise doses that were detected are potential doses. As shown in Table 4 (Attachment 5), two samples were run on Technical personnel. The average potential exposure was 9.8% of the Louisiana Oivlsion Guideline. 2. Area Surveys As shown in Attachments 6-8, the high noise areas 090 dbA) are the fluid bed dryer areas; the air compressor area; the 601, 602, and 603 blower areas; Blowers 1A and 2A, Blowers 105 and 205, and the cyclone blowers areas. All of the high noise areas listed above are designated ear protection areas. The perimeters of these areas are posted with high noise warning signs and employees are informed of these areas annually in the Industrial Hygiene Safety Meetings. TETRAHYDROFURAN EXPOSURE EVALUATION Guidelines and Sampling Method The ACGIH Threshold Limit Value (TLV-TWA) for tetrahydrofuran is 200 ppm with a TLV-STEL of 250 ppm. The TLV-STEL is a 15 minute exposure guideline. The 3M organic vapor monitor badge (#3500) was used to obtain breathing zone samples of operators performing pH test on CPE resin using tetrahydrofuran. The badges, which use an activate charcoal wafer as a collection medium, were desorbed with carbon disulfide and analyzed by gas chromatography. Discussion of Results As shown on Table 3 (Attachment 4) the personnel samples were below the 250 ppm TLV-STEL. Of the four (4) samples that were run only one was above the detection limits of 10.2 ppm. This sample was on an Outside S.O.T. and equalled 104.6 ppm for 15 minutes. DO 105714 CONFIDENT! Al CPE Industrial Hygiene Survey April 9, 1985 Page 6 The average concentrations that were detected are as follows: Sob ______ Sob_________Classification Resin pH Test Lab S.O.T. Resin pHTest Outside S.O.T. Number of Samples 2 2 Average Concentrati n Detected <10.2 ppm 56.6 ppm Mark D. Ryland Environmental Specialist Plastics Department Building 807 Attachments (8) ltb DO 105715 CONFIDENTIAL 00 105716 confidential WTACHHENT 1 SAMPLING DURATION (HINUTES) TABLE 1 EMPLOYEE'S TIME-WEIGHTED AVERAGE POTENTIAL EXPOSURES TO CHLORINE AT THE CPE PLANT, 1984 CHLORINE CONCENTRATION, PPM (VOL,VOL) EMPLOYEE 15 TIME WEIGHTED 30B NUMBER INSTANTANEOUS MINUTES AVERAGE OSHA PERMISSABLE EXPOSURE LIMIT (CEILING) 360 DAY MAINTENANCE 261 DAY MAINTENANCE 366 OUTSIDE S.O.T. 372 OUTSIDE S.O.T. 390 OUTSIDE S.O.T. 303 OUTSIDE S.O.T. 433425 434134 433363 433363 434002 433425 1.0 4.75 >12.00 0.15 1.20 1.35 5.80 0.07 1.27 0.00 0.02 0.03 0.01 0.00 0.11 0.00 0.00 0.00 0.00 MDR/itb 4-9-83 CONTROL ROOM CPE AREA CHLORINE SAMPLES, PPM (Vol ,Vol) %t>lH Unit ATTACHFtNT 2 DO 1 0 5 7 1 8 CO NFID ENTIAL ATTACHMENT 3 TABLE 2 EMPLOYEE'S TIME-WEIGHTED AVERAGE POTENTIAL EXPOSURES TO OUST AT THE CPE PLANT, 1904 SAMPLING duration (MINUTES) SAMPLE VOLUME (LITERS) DOB EMPLOYEE NUH3ER TIME WEIGHTED AVERAGE POTENTIAL2, EXPOSURE TO DUST1 RESPIRABLE DUST 1 TOTAL DUST ACGIH 1LV FOR NUISANCE DUST 1 ACGIH TLV FOR NON-ASBESTOS TALC 16 20.2 HOUSEKEEPING 180 304 HOUSEKEEPING 35 63 HOUSEKEEPING 38 60.4 OPERATING BAG SLITTER 41 73.8 OPERATING BAG SLITTER 36 63.0 OPERAITNG BAG SLITTER 43 73.1 OPERATING BAG SLITTER 40 68 OPERATING BAG SLITTER 434020 432698 434291 434133 434133 434291 434133 434133 5.0 2.0 3.5 1.5 <1.6 1.5 4.1 3.2 4.1 1.5 10.0 14.1 7.1 4.8 7.4 5.5 4.8 5.5 7.4 i i 1 CPE resin, calcium carbonate, non-asbestos talc. 2 An approved dust mask is required to be worn when performing these jobs. MDR/ltb 4-9-05 DO 1 0 5 7 1 9 CO NFIDENT! ATTACHMENT 4 TABLE 3 EMPLOYEE'S TIME-WEIGHTED AVERAGE POTENTIAL EXPOSURES TO TETRAHYDROFURAN AT THE CPE FT.ANT, 1984 <E SAMPLING DURATION (HINUTES) SAMPLE VOLUME (LITERS) OB1 ACGIH THRESHOLD LIMIT VALUE - STEL (15 MIN) 15 0.6 OUTSIDE S.O.T. 18 0.7 OUTSIDE S.O.T. 15 0.6 LAB S.O.T. 15 0.6 LAB S.O.T. EMPLOYEE NUMBER 434205 434020 433998 434040 TIHE WEIGHTED AVERAGE EXPOSURE, PPM (VOL,VOL) TETRAHYDROFURAN 250.0 104.6 <8.7 <10.2 <10.2 1 These excursion samples were taken while the operator was performing a routine pH test on CPE resin using T trahydrofuran. MBR/itb 4-9-85 DO 1 0 5 7 2 0 CO NFIDENTIAL ATTACHMENT 5 TABLE 4 EMPLOYEE'S TIME-WEIGHTED AVERAGE POTENTIAL EXPOSURES TO NOISE AT THE CPE PLANT, 1984 SAMPLING DURATION (MINUTES) 306 EMPLOYEE NUMBER POTENTIAL EXPOSURE > 115 db(A) TIME WEIGHTED AVERAGE EXPOSURE, PERCENT OF ALLOWABLE DOSE DOSE % OSHA REGULATION1 DOSE X 90 db(A) 'THRESHOLD2 DOSE % LOUISIANA DIVISION STANDARD3 407 TECHNICAL 420 TECHNICAL 432332 433955 NO NO 7.2 2.6 2.2 14.4 1.0 5.2 1 90 db(A) for 8 hours using an 80 db Threshold. 2 90 db(A) for 8 hours using a 90 db Threshold. ^ 85 db(A) for 8 hours using an 80 db Threshold. HDR/ltb 4-9-85 3/85 TRAIN I - UP5TAIRS AREA NOISE LEVELS (dbA) BL BL Do 105722 CONFIDENT]-, > > -<Jr 3 ON - BL106D 'ATTACHJCNT 7 TRAIN I I - SECOND DECK AREA NOISE LEVELS - (dbA) So Zo -n om ooi z "-1 -t-1H ttoo 3>