Document 0Jj82GRvaYxZqonMByknRBbXO

Interoffice ttemraiNlin TO |Hmi and tMitwi) 0. W. Schnellenberger PROM {NIH KM LKIIIMI * N. A. Flaten/J. H. Pritchard UNITERM CORY Q\1 OKN M (KCVA/74) OATC 12-15-82 REFERENCE NO. NAF-28/JHP-12-82 MS409 FEEDER CLEANING MONITORING RESULTS SUMMARY During production runs on MS409, the feed blend feeder is opened up and cleaned once per shift. This is to prevent a buildup of dust on the feeder belt and scales from causing feeder inaccuracy. Some of the products produced on MS409 contain asbestos and antimony trioxide (SbjOj). At the request of the Operations Department, per sonnel were monitored to determine if the feeder cleaning poses an asbestos and SbjOj exposure problem. The feeder cleaning was monitored twice. The procedure utilizes ' a portable vacuum cleaner.to remove and contain material from the feeder. The results show that none of the exposures exceed the OSHA or Celanese limits. The personal exposures to asbestos ranged from 0.06 to 0.43 fibers/cc versus an OSHA permissible exposure limit of 10.0 fibers/cc STEL. The personal exposures to SbaOi ranged from 0.002 to 0.007 mg/m1 for an eight hour TWA. The OSHA and Celanese limits for a TWA exposure to SbiOi are 0.5 and 0.15 mg/m1. The exposure data and feeder cleaning procedure was reviewed with the SHE Department. It was concluded that the present feeder cleaning procedure which utilizes a vacuum approved for use on asbestos is acceptable. This is consistent with the current Bishop Plant Policy for the Safe Handling and Disposal of Asbestos (Section VIX-4). Personnel should continue to follow this policy, particularly the protective equipment requirements, to ensure chat exposures to asbestos and SbaOj are minimized. Please review the exposure data with the personnel involved and post the data on your bulletin board. DISCUSSION During production runs on MS409, the feed blend feeder (HFE-226) must be opened up and cleaned. The feeder must be cleaned because a buildup of dust on the feeder belt and scale cause Inaccuracy in feeder performance resulting In 'ash* quality problems. Prior to 1982, tne feeder was cleaned only after ash problems arose. Earlier this year, a once per shift cleaning frequency was established to prevent off-specificatlon production due to ash.1 121468 FEB 17H jtaaoHtM, ,{^^Sj^S^6SBSiSS3KlSU^^BB NAF-28/JHP-12-82 2 December 15, 1982 Some of the Celanex products made on MS409 contain asbestos and SbjO). The feed blends which pass through the feeder contain approximately 42 asbestos and 5-82 SbjOj. Because the feeder cleaning has been changed from an infrequent to a once per shift task, there is a higher potential for employee exposure to asbestos and SbiOj. At the request of 0. W. Schnellenberger, personnel were monitored for exposure to asbestos and SbrO$ when cleaning the MS409 feed blend feeder. On August 30, 1982 and September 21, 1982, personnel and area samples were collected while the feed blend feeder was cleaned. During both clean-up procedures, the Nilfisk vacuum cleaner was used to remove and contain residual material from the feeder. The asbestos and SbiO* samples were collected and analyzed according to N10SH method P&CAM 239 and 52. The personnel exposure to asbestos ranged from 0.06 to 0.43 flbers/cc STEL. The personnel exposures to SbiOi were 0.002 and 0.009 mg/m* 8hr. TWA. The area samples showed airborne asbestos levels to range from 0.07 to 0.32 fibers/ cc and SbiOj levels to be 0.32 mg/m* (Table I and II). None of the exposures exceeded OSHA or Celanese permissible exposure limits. The OSHA short term exposure limit (STEL) for asbestos is 10 fibers/cc. The OSHA limit for SbiOs is 0.5 mg/m* for an 8 hr. TWA exposure. Celanese has established an exposure limit of 0.15 mg/m* 8 hr. TWA for SbjOj.1 Neither OSHA or Celanese specifies a STEL for SbiOj. Samples were taken only while personnel were cleaning the feeder (STEL type samples). Therefore, to make comparisons to the OSHA and Celanese SbxOi 8 hr. TWA limits, 8 hr. TWA exposures were calculated from the short term sample data and the assumption that employees were not exposed to Sb*0 during the rest of the shift. Current monitoring results indicate that this is a valid assumption because all 8 hr. TWA samples collected have been less than 0.07 mg/m*.* It should be noted that all personnel monitored were wearing dust masks and gloves. Therefore, actual concentrations of exposures to these compounds were less chan what is shown in Tables I and II. The exposure data and feeder cleaning procedure was reviewed with the SHE Department. It was concluded chat the present feeder cleaning procedure is acceptable. This procedure utilizes a Nilfisk vacuum cleaner which is approved for use with asbestos. The vacuuming technique is the method of choice because exposures were found to be low and had little variability. This procedure is consistent with the current Bishop Plant Policy for the Safe Handling and Disposal of Asbestos (Section VII-4). Personnel should continue to follow this policy. They should also continue to use the 3M 9910 dust mask and other protective equipment as required by the policy. The feeder cleaning procedure will be monitored periodically to ensure that exposures to asbestos and Sb0i do not exceed permissible exposure limits. 000534 NAF-28/JHP-12-82 -3- December IS, 1982 CONCLUSIONS ASP RECOMMENDATIONS 1. Nona of the exposures exceed the OSHA or Celanese permissible exposure limits for asbestos and SbjOj. 2. The present feeder cleaning procedure which utilizes the Nilfisk portable vacuum to clean and contain the residual material from the feeder is acceptable. 3. The cleaning procedure is consistant with the current Bishop Plant Policy for the Safe Handling and Disposal of Asbestos (Section VII-4). A. Personnel should continue to use the required protective equipment. The SHE Department recommends the 3M 9910 type dust mask. 5. The feeder cleaning procedure will be monitored periodically to ensure that exposures to asbestos and SbjOj do not exceed permissible exposure limits. REFERENCES 'Schnellenberger, 0. W., MS383/MSA09 Feeder Cleaning. August 31, 1982 (OWS-91-82). 'Barret, C. D., Celaneses Policy on Handling Carcinogens, November 15, 19B"2~7CBff-"241-S2i. 'Monitoring results to be issued when the study is complete. NAF/JHP/lat cc: R. C. Brandt E. J. Heinz R. C. Hilbrich H. W. Hill C. Ilia U. Hn*. Mneyyeri A. B. Milam D. A. Rack V. R. Tinsnan C. A. Amond S. Cregorcyk D. L. Wallen File: 1060.1 C. D. Barrett - Dallas D. Unrue - Louisville Central Files (3) CCCTC Uniterms Asbestos Antimony Monitoring Filled Resins Environmental 1982 Bishop 000535 MONITORING RESULTS DURING 9 -2 1 -8 2 FEED BLEND FEEDER CLEANING MONITORING RESULTS DURING 8 -2 0 -8 2 FEED BLENDER FEEDER CLEANING ths re st o f eh* s h ift 000537